emulating post install scripts in MacPorts?

[Jack Howarth]

    Am I correct to assume that, unlike fink, MacPorts doesn't
have the ability to execute post-installation scripts from
a binary archive? I ask because the authors of the apbs software
have asked that the following notice be given on installing
the software...

echo "+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++"
echo "Please issue \"open http://agave.wustl.edu/apbs/download/\","
echo "to register your use of this software to help the author"
echo "maintain funding for apbs.  apbs is released under the GPL and this is"
echo "not required, but would be very helpful."
echo "+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++"

The only approach I currently see in MacPorts is to use a post-destroot
phase to print that, however this won't address binary archives. The only
approach for those I see is to have a empty text file installed by apbs
which a startup script would check for content. If empty, it would be filled
with some text and the license message printed. I'd rather not have to
resort to that though. Thanks in advance for any hints on this issue.
                    Jack