Hello James, Alessio, anyone else I've figured out how to modify a package file and have created a custom gramps .deb that only requires python2.6.
Then I had a problem installing it, which pointed me at Python Central, which ships pyversions.py, that only supports 2.4 and 2.5. I modified that file on my machine to include python2.6. Now GRAMPS installs and runs cleanly. I've notified Michael Vogt about this directly in an email. Hope I'm not wasting any of your time. Jeff