[CentOS] rootpw and graphical mode?

Is there some kind of caveat to using the rootpw --iscrypted directive
and then specifying a graphical install?

I always seem to get the prompt coming up...
If I remove the graphical and do a text install, it works fine and if
I remove the --iscrypted  and put a plain-text password in there, it
works as well.

Any suggestions?

- G