Patch tool

Hi guys,
Just finished some hacking for evolution.

And now my problem:
It took some time testing so the official branch is now somewhat
different from my old checked out resources.
And in addition I fixed two seperate problems (again) and would like to
split up the patch.

This means that the patch between the new cvs and my original checkout
has 14000 lines and I would also need to split up the "real" changes
into two different patches.

How are you doing this?
Is there a tool to help me. Going through the patch by hand is rather
tiresome.

BR,
Ralf