NOGROUP undefined in Cred.c++

[Lim Kuan Siong <kslim@xxxxxxxxxxxxxx>]

Hi everyone,

I am trying to compile fam 2.6.9 on IRIX 6.5. However, I encounter the 
following error:
---------- Start of error ----------
cc-1020 CC: ERROR File = Cred.c++, Line = 97
  The identifier "NOGROUP" is undefined.

          primary_group = untrusted.is_valid() ? untrusted.gid() : NOGROUP;
                                                                   ^

1 error detected in the compilation of "Cred.c++".
---------- End of error ----------

I have searched the archive but did not see any posting that mentions this 
error. From the fam changelog, I noticed that "NOGROUP" was added in 2.6.8. 
I would be grateful if someone would point me in the right direction so 
that I can correct this error.
BTW, I tried to compile fam using g++ by setting the environment variable 
CXX to g++ but the configure script still uses "cc" as the C++ compiler. Is 
there a method of getting the script to use g++ instead?
Thank you very much in advance for any help.

Regards,
Kuan Siong Lim
Bioinformatics Centre,
National University of Singapore