Import error on QNX 6.2.1

I installed pyPgSQL on a QNX 6.2.1 machine. I already 
installed Python 2.2.1 as PostgreSQL 4.1.10, both of them 
run normally.
The installation of pyPgSQL ran normally, but when I try to 
start the pyPgSQL example I have the following message :

bash-2.05a# python test/PgSQLTestCases.py
Traceback (most recent call last):
  File "test/PgSQLTestCases.py", line 89, in ?
    from pyPgSQL import PgSQL
  File "/usr/lib/python2.2/site-packages/pyPgSQL/PgSQL.py", line 391, in ?
    from libpq import *
  File "/usr/lib/python2.2/site-packages/pyPgSQL/libpq/__init__.py", line 
23, in ?
    from libpq import *
ImportError: Library cannot be found
bash-2.05a#

It seems that pyPgSQL needs the library libpq.so, but the only one I have 
is in the lib directory of PostgreSQL '/usr/local/pgsql/lib'.

I tried to put libpq.so in the python lib-dynload directory, but the 
result is the same.

Do you have any idea on what I could do ?