How to remove inactive ports?

[Joachim Osnabryg]

In the http://guide.macports.org/ I can't find, how to uninstall incactive  
ports.
I see, when upgrading on or all, one can use $  port -u upgrade outdatet  
(or a single port),
but if I forgot to set the -u option, it serves nothing making another $   
port -u upgrade …

So I have e. g.:

$ port installed
The following ports are currently installed:
   apple-gcc42-devel @5564_0+darwin_8 (active)
   apr @1.3.9_1 (active)
   apr-util @1.3.9_1 (active)
   […]
   automake @1.10.2_0
   automake @1.11.1_0 (active)
   automoc @0.9.88_1 (active)
   bison @2.4.1_0 (active)
   bzip2 @1.0.5_1
   bzip2 @1.0.5_2
   bzip2 @1.0.5_3+darwin (active)
   [… …]

In the given cutout, I suppose that
   automake @1.10.2_0
   bzip2 @1.0.5_1
   bzip2 @1.0.5_2

are not longer used by other ports, so they could be removed, isn't it?

With which command can the inactive (meanwhile updated) ports be removed?

joachim
-- 
MacBook Pro intel OSX 10.4.11 Tiger