As I see from JBSEAM-758 I'm not the only one struggling with making a patch that only shows the lines that actually have changed.
Can't readily tell from looking at that patch what has changed.
Took me a while a couple of weeks ago to get a patch "right" myself.
I'd be submitting more patches if I would have that diff problem under control.
Cause appears to be some linefeeds submitted in the past to the CVS server, that's my best guess after Google searches.
Sure looking forward to this project (Seam) switching to Subversion, or the problem going away somehow (automated resubmit of all files with correct line feeds?).
I'm using JBoss IDE and its built-in support for CVS (on Windows XP).
Try installing cygwin and using the commandline CVS client.