I want to remove python2.4, but keep python2.5.

There's a s*** ton of python2.4 virtual packages. If I go in & purge the package that includes them, it typically breaks a python2.5 package as well.

Do I need to purge all of python2.4/2.5 then reinstall python2.5 or is there a better way?

at the end of the day, I'm trying to resolve this issue with trac:

I believe it has something to do with a python2.4/2.5 mixup in the distutils module. This started happening one day after I did an apt-get upgrade. Worked fine before, now trac doesn't work. If anyone has a clue on either issue, I'd be much obliged.

You can use the -s switch with aptitude ("s" for simulate) and try out any command you like without committing yourself to any change. aptitude finishes by telling you what it would do but it doesn't do anything. When you a command that does what you like you can then rerun aptitude without the -s switch (and as root) and it will actually perform the operation.
So you could test out this:
and if you're happy with the result. Run the command as normal.
cheers,
jdk

Thanks for the reply. I'm familiar with that option, but I don't think it answers the question.

Still wondering how to remove all things python2.4. I've a tried to simply remove the python2.4 package (granted, using aptitude rather than apt-get) and it didn't let me - too many dependencies... so I've been trying to remove each of those dependencies one by one. I think I've gotten all of them, but before I give it the go ahead (which will likely break python2.5 as well, though that can be fixed), I'd like to see if someone's done this before & can tell me a better way or confirm this is the correct way.

so what wrong with removing 2.4 then re-installing 2.5 if necessary ?

aptitude purge python2.4
aptitude install python2.5

Unless you've been mixing and matching your use of package management programs (apt-get, aptitude, etc..), removing 2.4 shouldn't remove any dependencies needed for 2.5