Problems calling external C routines from PL/SQL

Hi everybody!

I'm not familiar with C programming in Unix, but I'm trying to make work an example to execute external procedures (developed in C) from PL/SQL.
The example includes .c and .pc source files, which I have compiled succesfully.
After that, links the .o files into .so to declare later as libraries in the Oracle database.

The problem appears when I try to execute this procedures (from PL), when a I get the error:

"Error loading external library"
"ORA-06522: ld.so.1: ORACLE_HOME/bin/extprocPLSExtProc: fatal:
relocation error: file /opt/mqm/lib/libmqm.so: symbol NULL_HSHMEMS: referenced symbol not found"

The library /opt/mqm/lib/libmqm.so is provided with the installation of MQSeries Server.

Does anyone know whereelse can I find answers about this problem?

Thanx in advance.
Luisa.