Very Computer

Hello!
    I have a program with multiple threads. One thread (maintenance thread)
flushes unused data from the system and then fall asleep ( sleep() ) in a
loop. The other thread waits for external requests ( coming in through
Visigenic CORBA). While request arrives it creates new thread that processes
the request. The problem is that I find thread creating function
 pthread_create() ) waiting for sleeping function ( sleep() ) from the
maintenance process to complete. It looks like sleeping function blocks
thread-creating function. I've made a short example and it works fine but
the full application doesn't.
Does anyone know what could possible be wrong about the full application?
All suggestions will be appreciated.
                     Regards, Leszek Leszczynski
I use:
AIX 4.2
CORBA Visigenic 3.3.3
C++ compiler (newest)