Why problems with mount and strace

["Blizbor (IMA)" <tb670725@xxxxxx>]

Hi,

I have tested something and I have found weird behaviour.

I repeated the same for fstype in ext2, jfs, reiserfs and xfs curious 
how mkfs and mount
are working (trying to trace whats wrong beetween drbd and xfs)

strace -o mkfs.${fstype}.txt -ff mkfs.${fstype} /dev/xxx
strace -o mount.${fstype} /dev/xxx /mountpoint

I've got all mkfs logs.
I've got all but xfs logs for mount.

Telling the trueth, I've got log of mounting xfs but something weird 
happened.
Mount without strace was working fine but "strace mount" was failed.
(No such device, bad options ... easy to reproduce)
Why I can't mount xfs and strace it ?

Regards,
Blizbor