splitting a diff

I have a diff file that has changes to multiple source files that I want to split up for sending upstream. Is there a good tool for splitting this? The ideal would be something that takes a list of source files on the command line, and writes the diffs for them to one file and the diffs for everything else to another. -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/