The dependancies on this latest deb are very restrictive and have caused issues for me as well.
The new wwwconfig-common dependency means that this deb is no longer supported with Ubuntu 8.04.
$ sudo dpkg -i postfixadmin_2.3rc5_all.deb
Selecting previously deselected package postfixadmin.
(Reading database ... 25961 files and directories currently installed.)
Unpacking postfixadmin (from...
2009-06-22 00:14:39 UTC in Postfix Admin
