[HACKERS] pg_connect error

I'm trying to use the php/postgresql interface via my apache server.
When I try and load a page containing:

<?php $db = pg_connect( "database=mydb owner=me" )
     or die ( "could not connect" ) ?>

(both the database and owner are valid and tested via psql)

apache complains:
/usr/libexec/ld.so: Undefined symbol "_PQconnectdb" called from httpd:/usr/lib/apache/modules/libphp4.so at 0x4030a394

I have verified through ldconfig that libpq.so.2.0 is being loaded into hints,
what am I missing?

Thanks,
 edge