EXTRA_PATCHES considered harmful?

[Julian Elischer]

currently if you set EXTRA_PATCHES and the port you are making decides 
to build a second port as a dependency, EXTRA_PATCHES is passed to the 
second port which them obiously fails to patch it.

e.g.  cd /usr/ports/emulators/open-vm-tools-nox11; Make 
EXTRA_PATCHES=/foo/bar/patch1

will fail when it tries to apply the patch files to each dependency.

AM I doing something wrong here?