How to check for memory leaks in Delphi ISAPI module?

I'm writing a Delphi ISAPI module as part of my internship. I'm not a seasoned programmer by far, but I've managed to write something that's useful in the light of my assignment.

Before migrating it to a production-environment, I'd like to test the module for memory leaks. Does any of you have any tips on how to do this? I've done a manual code review and asked a more experienced colleague to do the same, but still we could have missed something.

There are several packages out there that'll automate this, but they're all focusing on stand-alone applications, not IIS modules. Apart from that, can you be sure that a test application will walk all possible paths through the software?