BUG: 'port uninstall' does not remove entry in dependency list.

[agentmonkey@…]

After going through a few upgrades via "port -a upgrade" I noticed that the upgrades only deactivated older versions of packages. After uninstalling the inactive ports manually (I needed to use -f since inactive ports can still have dependents) I noticed that their entries in the "dependency list" are not removed. For example:

~ $ sudo port installed | grep apr
  apr @1.2.6_0 (active)
  apr-util @1.2.6_0 (active)
-= rom@leviathan =- Sun May 07, 02:00 AM 
~ $

then,

-= rom@leviathan =- Sun May 07, 02:00 AM 
~ $ sudo port uninstall apr
Password:
--->  Unable to uninstall apr 1.2.6_0, the following ports depend on it:
--->    apr-util
--->    apr-util
--->    apr-util
--->    subversion
--->    subversion-javahlbindings
Error: /opt/local/bin/port: port uninstall failed: Please uninstall the ports that depend on apr first.
-= rom@leviathan =- Sun May 07, 02:16 AM 
~ $ 

Notice that apr-util appears three times but in the former command only one apr-util package is shown to be installed (apr-util @1.2.6_0). These "residual" packages are from previous inactive versions (because of upgrades) that were manually uninstalled.