[Zope] ZPygreSQL woes

I've run into a problem with Zope with PostgreSQL. The query runs and runs and runs till all the memory on the server is used up and Zope falls over. Everything works fine on a small table but comes apart as the number of fields in a table increases. For example, the table that I'm trying to query has 18 fields. I'm running postgresql-6.4.2, the ZPygreSQLDA is straight off of the Zope site. I've tried Zope versions from 1.10 all the way up through 2.0.0b1. Has anyone else had this problem? This is a very serious issue for me. Any help would be greatly appreciated if I'm doing something wrong.