Comment 9 for bug 392143

Fabrice, here is the answer from Debian maintainer regarding the removal of the link in postgis.postrm

"[...] That link is there to allow an upgrade path from one postgis
version to another (with the same postgresql version), the purge should be done only
if one is interested in cleaning all postgis versions to do not use postgis anymore,
it should not be removed when a specific postgis edition is purged (which could happen
if admin would be too hasty in doing its homework). I think this way of doing the
thing is a bit more safe, indeed."

However, now that it's fixed upstream we can sync from Debian (note that latest postgis doesn't build on armel and mips) and I backported the fix to Karmic.