How to write Patches for Phoenix which have side-effects in Mozilla

Hi!
I'm working on a bug, which intends to cut down the Phoenix/Firebird
classic.jar, which still carries a lot of Mozilla bloat, which isn't
needed in Phoenix/Firebird (the Composer and the Messenger UI for
example).

http://bugzilla.mozilla.org/show_bug.cgi?id=189043

The problem is, only the Phoenix/Firebird specific UI (Icons, forked
XUL/CSS) lies in mozilla/browser, all the other stuff lies in
mozilla/themes/classic and is used by Mozilla as well.

Currently the Phoenix/Firebird-specific UI and the Mozilla UI are
magically combined (at build time I guess) to a new classic.jar, which
includes all the Phoenix/Firebird-specific classic.jar stuff and the
normal Mozilla classic.jar

So how do I write a patch, removing lots of stuff for Phoenix/Firebird. A
simple patch, removing the unused UI from mozilla/themes/classic and its
subdirectories and cutting down the jar.mn file would affect Mozilla
also, wouldn't it?

BTW I have opened another similar bug for Phoenix/Firebird comm.jar
http://bugzilla.mozilla.org/show_bug.cgi?id=200142 for which everything
applies as well.

I already asked in netscape.public.mozilla.qa.general, but didn't get any
answers. Followup-To is set to npmqb.

Any help would be greatly appreciated
Simon
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Linus: You suicidal?
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