The man page for the sigwait function, i.e., pthread_signal(3), which is in the glibc-devel package, claims, "The sigwait function never returns an error." This is simply not true, as a quick glance at linuxthreads/sysdeps/unix/sysv/linux/sigwait.c will prove. A further glance at kernel/signal.c in the kernel sources will give you an indication of what errors sigwait can, in fact, return.
Fixed by removing all linuxthreads man pages except those that aren't covered in 3p section. http://sources.redhat.com/ml/glibc-cvs/2005-q2/msg00360.html Will show up in next glibc build.