limiting installed (re)versions in port?

[Jack Howarth]

  One aspect of MacPorts that concerns me (compared to
fink) is that it seems possible with port to accumulate
a huge number of installed (but deactivated) package
(re)versions over time. I can understand the concept of
keeping some of the most recent (re)versions but not
every single one. It would make much more sense to adopt
the approach where only those previous (re)versions would
be kept up to some user defined limit (perhaps defaulting
to 2 or 3 previous (re)versions of the same package).
When a new (re)version of the same package is installed 
and the limit of archived (re)versions has been meet,
the oldest copy would be purged from the system. Otherwise
the numbers of deactivated ports will bloat the system
over time. Has a ticket ever been opened for such a feature
in port?
             Jack