Using one connection object.

Hi,
I am using postgresql 7.2 on red hat linux.I am having only one connection to the database thro
PGconn(struct pg_conn ) which serves all the clients. I understand that PGconn is not thread safe.
So from my program I am having mutexes to protect PGconn from multiple access by 2 or more threads.

Using this model execution goes thro for around 20/30 queries. After that somehow ExecTuplesOK() call from one thread is blocking for some reason because of which other threads are not able to proceed. (Pls note I have protected call to ExecTuplesOK() using mutex so that only one thread can enter it.)

If anybody has any idea pls let me know..

Thanks in advance
Sankarshana M