internal-to-Portfile variable during upgrade?

[Michael Dickens]

On Thu, 08 Jul 2010 16:07 +0200, "Rainer Müller" <raimue at macports.org>
wrote:
> Ahhhh, sorry, I forgot one important thing... variants are evaluated
> *after* the rest of the Portfile (in order to resolve conflicts and
> requires first). So this configure.cmd is evaluated before the variants
> and therefore qt_dir is not set to what you expected.
> 
> If configure.cmd is all you want to change it would be way easier to
> just use this inside the variant directly.

Unfortunately for most ports, ${qt_dir} is needed for multiple tasks --
from setting the configure.cmd to doing reinplace in post-destroot to
...  so, I need it to be set correctly -before- those other tasks are
executed.  Any further ideas?  I'll also keep playing around to see what
I can come up with. - MLD