Error encountered when attempting to compile Mailman on 10.5.8 server

I mentioned in a previous post that the Mailman version shipped with Snow Leopard was not the release version but a release candidate. In an attempt to trial the upgrade on a Leopard server before doing on Snow Leopard, I encountered the following error when configuring it:

• Distutils is not available or is incomplete for /usr/bin/python

Here is the version information I have on Python:

• Python 2.5.1 (r251:54863, Feb 6 2009, 19:02:12)
• [GCC 4.0.1 (Apple Inc. build 5465)] on darwin

Suggestions on how to proceed? I have marginal skills.

Paul