diff --git a/build/rpm/GNUmakefile b/build/rpm/GNUmakefile
index 0dcaf49..522b6a0 100644
--- a/build/rpm/GNUmakefile
+++ b/build/rpm/GNUmakefile
@@ -64,7 +64,7 @@ pcp.spec: pcp.spec.in
 	    -e's|@pmda_infiniband@|$(PMDA_INFINIBAND)|g' \
 	    -e's|@enable_secure@|$(ENABLE_SECURE)|g' \
 	    -e's|@enable_probes@|$(ENABLE_PROBES)|g' \
-	    -e's|@enable_dns_sd@|$(ENABLE_DNS_SD)|g' \
+	    -e's|@enable_avahi@|$(ENABLE_AVAHI)|g' \
 	    -e"s|@build_root@|$${DIST_ROOT}|g" \
 	    -e's|@pcp_sysconf_dir@|$(PCP_SYSCONF_DIR)|g' \
 	    -e's|@pcp_log_dir@|$(PCP_LOG_DIR)|g' \
diff --git a/build/rpm/pcp.spec.in b/build/rpm/pcp.spec.in
index e8e6183..3c5b0b6 100644
--- a/build/rpm/pcp.spec.in
+++ b/build/rpm/pcp.spec.in
@@ -13,7 +13,7 @@ BuildRequires: python-devel
 BuildRequires: ncurses-devel
 BuildRequires: readline-devel
 BuildRequires: perl(ExtUtils::MakeMaker)
-%if "@enable_dns_sd@" == "true"
+%if "@enable_avahi@" == "true"
 BuildRequires: avahi-devel
 %endif
 %if "@enable_secure@" == "true"
diff --git a/configure b/configure
index 8664890..0dc1bb2 100755
--- a/configure
+++ b/configure
@@ -774,7 +774,7 @@ PACKAGE_MINOR
 PACKAGE_MAJOR
 pcp_platform_paths
 enable_avahi
-enable_dns_sd
+enable_discovery
 lib_for_avahi
 avahi_LIBS
 avahi_CFLAGS
@@ -859,7 +859,7 @@ with_static_probes
 with_infiniband
 with_user
 with_group
-with_dns_sd
+with_discovery
 enable_ssp
 enable_pie
 enable_shared
@@ -1528,8 +1528,7 @@ Optional Packages:
   --with-user             user account under which daemons run (default is
                           pcp)
   --with-group            user group under which daemons run (default is pcp)
-  --with-dns-sd           enable support for DNS Service Discovery (default is
-                          on)
+  --with-discovery        enable support for service discovery (default is on)
   --with-configdir        configuration directory [LOCALSTATEDIR/pcp/config]
   --with-perl_installdirs perl installdirs [vendor]
   --with-perl_install_base
@@ -2481,11 +2480,11 @@ fi
 
 
 
-# Check whether --with-dns-sd was given.
-if test "${with_dns_sd+set}" = set; then :
-  withval=$with_dns_sd; do_dns_sd=$withval; PACKAGE_CONFIGURE="$PACKAGE_CONFIGURE --with-dns-sd=$withval"
+# Check whether --with-discovery was given.
+if test "${with_discovery+set}" = set; then :
+  withval=$with_discovery; do_discovery=$withval; PACKAGE_CONFIGURE="$PACKAGE_CONFIGURE --with-discovery=$withval"
 else
-  do_dns_sd=check
+  do_discovery=check
 fi
 
 
@@ -4190,7 +4189,7 @@ $as_echo "no" >&6; }
 		PKG_CONFIG=""
 	fi
 fi
-if test "x$do_dns_sd" != "xno"; then :
+if test "x$do_discovery" != "xno"; then :
 
     # on Mac OS X, dns_sd.h
 
@@ -4364,13 +4363,18 @@ done
 
 	$as_echo "#define HAVE_AVAHI 1" >>confdefs.h
 
-	enable_dns_sd=true
+	enable_discovery=true
     fi
 
-    if test "$do_dns_sd" != "check" -a "$enable_dns_sd" != "true"
+    if test "$do_discovery" != "check" -a "$enable_discovery" != "true"
     then
         as_fn_error $? "cannot enable DNS-SD - no platform support" "$LINENO" 5
     fi
+    if test "$enable_discovery" = "true"
+    then
+        $as_echo "#define HAVE_SERVICE_DISCOVERY 1" >>confdefs.h
+
+    fi
 
 fi
 
diff --git a/configure.in b/configure.in
index 847d69a..7759220 100644
--- a/configure.in
+++ b/configure.in
@@ -78,11 +78,11 @@ AC_ARG_WITH(
     [pcp_group=pcp])
 AC_SUBST(pcp_group)
 
-AC_ARG_WITH([dns-sd],
-    [AC_HELP_STRING([--with-dns-sd],
-                   [enable support for DNS Service Discovery (default is on)])],
-    [do_dns_sd=$withval; PACKAGE_CONFIGURE="$PACKAGE_CONFIGURE --with-dns-sd=$withval"],
-    [do_dns_sd=check])
+AC_ARG_WITH([discovery],
+    [AC_HELP_STRING([--with-discovery],
+                   [enable support for service discovery (default is on)])],
+    [do_discovery=$withval; PACKAGE_CONFIGURE="$PACKAGE_CONFIGURE --with-discovery=$withval"],
+    [do_discovery=check])
 
 #
 # Note: the following environment variables may be
@@ -248,8 +248,8 @@ then
     AC_SUBST(DTRACE)
 fi
 
-dnl Check for DNS-SD (Service Discovery)
-AS_IF([test "x$do_dns_sd" != "xno"], [
+dnl Check for service discovery mechanisms (DNS-SD, Avahi)
+AS_IF([test "x$do_discovery" != "xno"], [
     # on Mac OS X, dns_sd.h
 
     # on Linux, aloha Avahi
@@ -267,15 +267,19 @@ AS_IF([test "x$do_dns_sd" != "xno"], [
 	AC_SUBST(lib_for_avahi)
 	AC_SUBST(avahi_CFLAGS)
 	AC_DEFINE(HAVE_AVAHI)
-	enable_dns_sd=true
+	enable_discovery=true
     fi
 
-    if test "$do_dns_sd" != "check" -a "$enable_dns_sd" != "true"
+    if test "$do_discovery" != "check" -a "$enable_discovery" != "true"
     then
-        AC_MSG_ERROR(cannot enable DNS-SD - no platform support)
+	AC_MSG_ERROR(cannot enable service discovery - no supported mechanisms)
+    fi
+    if test "$enable_discovery" = "true"
+    then
+	AC_DEFINE(HAVE_SERVICE_DISCOVERY)
     fi
 ])
-AC_SUBST(enable_dns_sd)
+AC_SUBST(enable_discovery)
 AC_SUBST(enable_avahi)
 
 # setup additional platform-specific binary search PATH components
diff --git a/src/include/builddefs.in b/src/include/builddefs.in
index e720112..b5a3c8a 100644
--- a/src/include/builddefs.in
+++ b/src/include/builddefs.in
@@ -191,7 +191,6 @@ RDYNAMIC_FLAG = @rdynamic_flag@
 ENABLE_SHARED = @enable_shared@
 ENABLE_SECURE = @enable_secure@
 ENABLE_PROBES = @enable_probes@
-ENABLE_DNS_SD = @enable_dns_sd@
 ENABLE_AVAHI  = @enable_avahi@
 
 # additional libraries needed for particular functions
diff --git a/src/include/pcp/config.h.in b/src/include/pcp/config.h.in
index d0b3e79..9f69ff5 100644
--- a/src/include/pcp/config.h.in
+++ b/src/include/pcp/config.h.in
@@ -193,8 +193,9 @@ extern "C" {
 
 /* define which libraries are available */
 #undef HAVE_SECURE_SOCKETS
-#undef HAVE_AVAHI
 #undef HAVE_STATIC_PROBES
+#undef HAVE_SERVICE_DISCOVERY
+#undef HAVE_AVAHI
 #undef HAVE_LIBREGEX
 #undef HAVE_READLINE
 
diff --git a/src/include/pcp/impl.h b/src/include/pcp/impl.h
index f7aa1cc..714e873 100644
--- a/src/include/pcp/impl.h
+++ b/src/include/pcp/impl.h
@@ -644,11 +644,10 @@ typedef enum {
     PM_SERVER_FEATURE_AUTH,
     PM_SERVER_FEATURE_CREDS_REQD,
     PM_SERVER_FEATURE_UNIX_DOMAIN,
+    PM_SERVER_FEATURE_DISCOVERY,
     PM_SERVER_FEATURES
 } __pmServerFeature;
 
-typedef struct __pmServerPresence __pmServerPresence;
-
 extern int __pmServerHasFeature(__pmServerFeature);
 extern int __pmServerSetFeature(__pmServerFeature);
 extern int __pmServerAddPorts(const char *);
@@ -663,6 +662,8 @@ extern int __pmServerOpenRequestPorts(__pmFdSet *, int);
 extern void __pmServerCloseRequestPorts(void);
 extern void __pmServerDumpRequestPorts(FILE *);
 extern char *__pmServerRequestPortString(int, char *, size_t);
+
+typedef struct __pmServerPresence __pmServerPresence;
 extern __pmServerPresence *__pmServerAdvertisePresence(const char *, int);
 extern void __pmServerUnadvertisePresence(__pmServerPresence *);
 
diff --git a/src/libpcp/src/auxserver.c b/src/libpcp/src/auxserver.c
index 556cb2b..c7f9635 100644
--- a/src/libpcp/src/auxserver.c
+++ b/src/libpcp/src/auxserver.c
@@ -697,6 +697,22 @@ __pmSecureServerHandshake(int fd, int flags, __pmHashCtl *attrs)
     return -EOPNOTSUPP;
 }
 
+int
+__pmSecureServerHasFeature(__pmServerFeature query)
+{
+    (void)query;
+    return 0;
+}
+
+int
+__pmSecureServerSetFeature(__pmServerFeature wanted)
+{
+    (void)wanted;
+    return 0;
+}
+
+#endif /* !HAVE_SECURE_SOCKETS */
+
 static unsigned int server_features;
 
 int
@@ -707,7 +723,7 @@ __pmServerSetFeature(__pmServerFeature wanted)
 	server_features |= (1 << wanted);
 	return 1;
     }
-    return 0;
+    return __pmSecureServerSetFeature(wanted);
 }
 
 int
@@ -719,28 +735,26 @@ __pmServerHasFeature(__pmServerFeature query)
     case PM_SERVER_FEATURE_IPV6:
 	sts = (strcmp(__pmGetAPIConfig("ipv6"), "true") == 0);
 	break;
+    case PM_SERVER_FEATURE_DISCOVERY:
     case PM_SERVER_FEATURE_CREDS_REQD:
     case PM_SERVER_FEATURE_UNIX_DOMAIN:
 	if (server_features & (1 << query))
 	    sts = 1;
 	break;
     default:
+	sts = __pmSecureServerHasFeature(query);
 	break;
     }
     return sts;
 }
 
-#endif /* !HAVE_SECURE_SOCKETS */
-
-/* XXX TODO: HAVE_SERVICE_DISCOVERY not defined yet. Waiting on Nathan.
- * For now, enable this code if we have Avahi. */
-#if HAVE_AVAHI /* defined(HAVE_SERVICE_DISCOVERY) */
+#if defined(HAVE_SERVICE_DISCOVERY)
 
 __pmServerPresence *
 __pmServerAdvertisePresence(const char *serviceSpec, int port)
 {
-    /* Allocate the server presence data structure. */
     __pmServerPresence *s;
+
     if ((s = malloc(sizeof(*s))) == NULL) {
 	__pmNoMem("__pmServerAdvertisePresence: can't allocate __pmServerPresence",
 		  sizeof(*s), PM_FATAL_ERR);
@@ -749,24 +763,20 @@ __pmServerAdvertisePresence(const char *serviceSpec, int port)
     /* Now advertise our presence using all available means. If a particular
      * method is not available or not configured, then the respective call
      * will have no effect.
-     * Currently, only avahi is supported.
      */
-    s->avahi = __pmServerAvahiAdvertisePresence(serviceSpec, port);
-
+    __pmServerAvahiAdvertisePresence(s, serviceSpec, port);
+    server_features |= PM_SERVER_FEATURE_DISCOVERY;
     return s;
 }
 
 void
-__pmServerUnadvertisePresence(__pmServerPresence *s) {
+__pmServerUnadvertisePresence(__pmServerPresence *s)
+{
     /* Unadvertise our presence for all available means. If a particular
      * method is not active, then the respective call will have no effect.
-     * Currently, only avahi is supported.
      */
-    if (s->avahi != NULL) {
-	__pmServerAvahiUnadvertisePresence(s->avahi);
-	free(s->avahi);
-	s->avahi = NULL;
-    }
+    __pmServerAvahiUnadvertisePresence(s);
+    free(s);
 }
 
 #else /* !HAVE_SERVICE_DISCOVERY */
diff --git a/src/libpcp/src/avahi.c b/src/libpcp/src/avahi.c
index d14a577..ce3620a 100644
--- a/src/libpcp/src/avahi.c
+++ b/src/libpcp/src/avahi.c
@@ -16,16 +16,17 @@
 
 #include "pmapi.h"
 #include "impl.h"
+#include "internal.h"
 #include "avahi.h"
 
-typedef struct __pmServerAvahiPresence {
+struct __pmServerAvahiPresence {
     char		*avahi_service_name;
     const char		*avahi_service_tag;
     int			port;
     AvahiThreadedPoll	*avahi_threaded_poll;
     AvahiClient		*avahi_client;
     AvahiEntryGroup	*avahi_group;
-} __pmServerAvahiPresence;
+};
 
 static void entryGroupCallback(
     AvahiEntryGroup *g,
@@ -301,13 +302,12 @@ publishService(const char *serviceName, const char *serviceTag, int port)
   return NULL;
 }
 
-__pmServerAvahiPresence *
-__pmServerAvahiAdvertisePresence(const char *serviceSpec, int port)
+void
+__pmServerAvahiAdvertisePresence(__pmServerPresence *s, const char *serviceSpec, int port)
 {
     size_t size;
     char *serviceName;
     char *serviceTag;
-    __pmServerAvahiPresence *p;
 
     /* The service spec is simply the name of the server. Use it to
      * construct the avahi service name and service tag.
@@ -327,15 +327,19 @@ __pmServerAvahiAdvertisePresence(const char *serviceSpec, int port)
     sprintf(serviceTag, "_%s._tcp", serviceSpec);
     
     /* Now publish the avahi service. */
-    p = publishService (serviceName, serviceTag, port);
+    s->avahi = publishService(serviceName, serviceTag, port);
 
     /* Clean up. */
     free(serviceName);
     free(serviceTag);
-    return p;
 }
 
 void
-__pmServerAvahiUnadvertisePresence(__pmServerAvahiPresence *s) {
-    cleanup(s);
+__pmServerAvahiUnadvertisePresence(__pmServerPresence *s)
+{
+    if (s->avahi != NULL) {
+	cleanup(s->avahi);
+	free(s->avahi);
+	s->avahi = NULL;
+    }
 }
diff --git a/src/libpcp/src/avahi.h b/src/libpcp/src/avahi.h
index bb548b4..78d4372 100644
--- a/src/libpcp/src/avahi.h
+++ b/src/libpcp/src/avahi.h
@@ -19,9 +19,7 @@
 #include <avahi-common/malloc.h>
 #include <avahi-common/error.h>
 
-typedef struct __pmServerAvahiPresence __pmServerAvahiPresence;
-
-__pmServerAvahiPresence *__pmServerAvahiAdvertisePresence(const char *, int);
-void __pmServerAvahiUnadvertisePresence(__pmServerAvahiPresence *);
+void __pmServerAvahiAdvertisePresence(__pmServerPresence *, const char *, int);
+void __pmServerAvahiUnadvertisePresence(__pmServerPresence *);
 
 #endif /* AVAHI_H */
diff --git a/src/libpcp/src/check-statics b/src/libpcp/src/check-statics
index f8030a3..35f3f24 100755
--- a/src/libpcp/src/check-statics
+++ b/src/libpcp/src/check-statics
@@ -99,7 +99,7 @@ auxserver.o
     b localSocketPath		# single-threaded server scope
     b serviceSpec		# single-threaded server scope
     d localSocketFd		# single-threaded server scope
-    b ?server_features		# single-threaded server scope
+    b server_features		# single-threaded server scope
 ?avahi.o
 checksum.o
 config.o
diff --git a/src/libpcp/src/config.c b/src/libpcp/src/config.c
index a2b5e3d..34d78b8 100644
--- a/src/libpcp/src/config.c
+++ b/src/libpcp/src/config.c
@@ -323,6 +323,11 @@ ipv6_enabled(void)
 #else
 #define STATIC_PROBES_ENABLED	disabled
 #endif
+#if defined(HAVE_SERVICE_DISCOVERY)
+#define SERVICE_DISCOVERY_ENABLED	enabled
+#else
+#define SERVICE_DISCOVERY_ENABLED	disabled
+#endif
 
 typedef const char *(*feature_detector)(void);
 static struct {
@@ -343,6 +348,7 @@ static struct {
 	{ "authentication",	AUTHENTICATION_ENABLED },	/* from pcp-3.8.x */
 	{ "unix_domain_sockets",UNIX_DOMAIN_SOCKETS_ENABLED },	/* from pcp-3.8.2 */
 	{ "static_probes",	STATIC_PROBES_ENABLED },	/* from pcp-3.8.3 */
+	{ "service_discovery",	SERVICE_DISCOVERY_ENABLED },	/* from pcp-3.8.6 */
 };
 
 void
diff --git a/src/libpcp/src/internal.h b/src/libpcp/src/internal.h
index ab76145..d0392b8 100644
--- a/src/libpcp/src/internal.h
+++ b/src/libpcp/src/internal.h
@@ -120,6 +120,8 @@ extern int __pmConnectCheckError(int);
 extern void *__pmGetSecureSocket(int);
 extern void *__pmGetUserAuthData(int);
 extern int __pmSecureServerIPCFlags(int, int);
+extern int __pmSecureServerHasFeature(__pmServerFeature);
+extern int __pmSecureServerSetFeature(__pmServerFeature);
 
 #define SECURE_SERVER_SASL_SERVICE "PCP Collector"
 #define LIMIT_AUTH_PDU	2048	/* maximum size of a SASL transfer (in bytes) */
@@ -152,9 +154,9 @@ extern int __pmGetUserIdentity(const char *, __pmUserID *, __pmGroupID *, int);
  */
 typedef struct __pmServerAvahiPresence __pmServerAvahiPresence;
 
-typedef struct __pmServerPresence {
+struct __pmServerPresence {
     __pmServerAvahiPresence	*avahi;
-} __pmServerPresence;
+};
 
 #ifdef __cplusplus
 }
diff --git a/src/libpcp/src/secureserver.c b/src/libpcp/src/secureserver.c
index c336341..223f68a 100644
--- a/src/libpcp/src/secureserver.c
+++ b/src/libpcp/src/secureserver.c
@@ -37,58 +37,28 @@ static struct {
     /* status flags (bitfields) */
     unsigned int	certificate_verified : 1;	/* NSS */
     unsigned int	ssl_session_cache_setup : 1;	/* NSS */
-    unsigned int	credentials_required : 1;	/* SASL/AF_UNIX */
-    unsigned int	unix_domain_socket : 1;		/* AF_UNIX */
 } secure_server;
 
 int
-__pmServerSetFeature(__pmServerFeature wanted)
+__pmSecureServerSetFeature(__pmServerFeature wanted)
 {
-    switch (wanted) {
-    case PM_SERVER_FEATURE_CREDS_REQD:
-	PM_INIT_LOCKS();
-	PM_LOCK(__pmLock_libpcp);
-	secure_server.credentials_required = 1;
-	PM_UNLOCK(__pmLock_libpcp);
-	return 1;
-    case PM_SERVER_FEATURE_UNIX_DOMAIN:
-	PM_INIT_LOCKS();
-	PM_LOCK(__pmLock_libpcp);
-	secure_server.unix_domain_socket = 1;
-	PM_UNLOCK(__pmLock_libpcp);
-	return 1;
-    default:
-	break;
-    }
-    return 0;
+    (void)wanted;
+    return 0;	/* nothing dynamically enabled at this stage */
 }
 
 int
-__pmServerHasFeature(__pmServerFeature query)
+__pmSecureServerHasFeature(__pmServerFeature query)
 {
     int sts = 0;
 
     switch (query) {
-    case PM_SERVER_FEATURE_UNIX_DOMAIN:
-    case PM_SERVER_FEATURE_CREDS_REQD:
     case PM_SERVER_FEATURE_SECURE:
-	PM_INIT_LOCKS();
-	PM_LOCK(__pmLock_libpcp);
-	if (query == PM_SERVER_FEATURE_SECURE)
-	    sts = secure_server.certificate_verified;
-	if (query == PM_SERVER_FEATURE_CREDS_REQD)
-	    sts = secure_server.credentials_required;
-	if (query == PM_SERVER_FEATURE_UNIX_DOMAIN)
-	    sts = secure_server.unix_domain_socket;
-	PM_UNLOCK(__pmLock_libpcp);
+	sts = secure_server.certificate_verified;
 	break;
     case PM_SERVER_FEATURE_COMPRESS:
     case PM_SERVER_FEATURE_AUTH:
 	sts = 1;
 	break;
-    case PM_SERVER_FEATURE_IPV6:
-	sts = (strcmp(__pmGetAPIConfig("ipv6"), "true") == 0);
-	break;
     default:
 	break;
     }