apt makes it easy to track the new package but hard to dump the old

[jidanni@jidanni.org]

Why do I always have to clean up older versions by hand?

E.g., linux-doc-2.6 pulls in the latest version automatically,
but if I don't want an ever growing number of older versions accruing, I
have to remove them by hand.

# apt-show-versions -r -p ^linux-doc
linux-doc-2.6/unstable uptodate 1:2.6.38+33
linux-doc-2.6.37 2.6.37-2 installed: No available version in archive
linux-doc-2.6.38/unstable uptodate 2.6.38-2

Sure 'do aptitude purge ~o often.' But that is still by hand.

Why does apt make it easy to add the new version but lacks facilities to
clean up the old versions? Safety yes. But still not environmentally friendly.