Unable to see symbols from libpthread

[Sripathi Kodi]

Hi,

I am trying to debug a program for which I need to get thread backtraces 
through gdb on a RHEL5 system (32 bit binary on x86_64). I installed 
glibc-debuginfo rpms, hoping to get more information from backtraces. 
While starting gdb, it says it read symbols from the debug library:

Reading symbols from /lib/libpthread.so.0...Reading symbols 
from /usr/lib/debug/lib/libpthread-2.5.so.debug...done.
[Thread debugging using libthread_db enabled]
[New Thread 4159912832 (LWP 6751)]
[New Thread 3815779216 (LWP 6961)]
[New Thread 3816045456 (LWP 6960)]
[New Thread 3816311696 (LWP 6959)]
[New Thread 3816577936 (LWP 6958)]
[New Thread 3816844176 (LWP 6957)]
[New Thread 3817110416 (LWP 6956)]
[New Thread 3817380752 (LWP 6955)]
[New Thread 3817646992 (LWP 6954)]
[New Thread 4155460496 (LWP 6953)]
[New Thread 4155427728 (LWP 6952)]
[New Thread 3818048400 (LWP 6951)]
[New Thread 4159867792 (LWP 6799)]
done.
Loaded symbols for /lib/libpthread.so.0

However, it does not show symbols from libpthread:

#1  0x43da3236 in pthread_cond_wait@@GLIBC_2.3.2 () 
from /lib/libpthread.so.0
No symbol table info available.


IIRC, I used to see line numbers and function parameters from libpthread 
in the past. What have I missed now? Can someone point me to how to see 
debug information from libpthread? I want to avoid compiling my own 
glibc just for this purpose.

Thanks,
Sripathi.