patching a build dependency

[Mars G. Miro]

Hi porters!

 I'm working on a port that has another port as its build dependency.
Let's say this is port X and the dependency is port Z. When I'm
building port X, I need to patch something in port Z, however I don't
need to patch port Z if i'm only building port Z. Is this at all
possible to set this in port X's Makefile? or should I do this in port
Z, then perhaps define a variable somewhere to patch it if i'm
building port X?

 Thanks much.


cheers
mars