Postfix packages older than 2.2.4-5mdk had a wrong triggerpostun script which made it difficult to change the alternatives scheme. Starting with 2.2.4-6mdk a new alternatives scheme is being used which is described best here: http://archives.mandrakelinux.com/cooker/2005-06/msg01987.php This introduced problems in the upgrade due to that old triggerpostun script. The main symptoms are broken symbolic links and missing binaries (like /usr/bin/mailq). Not all upgrades will have this problem: just the ones where a postfix package with the broken triggerpostun script is upgraded directly to postfix >= 2.2.4-6mdk. The init script in postfix >= 2.2.4-6mdk will correct most of the problems as soon as the service is (re)started, but the following manpages will not be accessible: mailq(1), newaliases(1) and aliases(5). A reinstallation of the postfix package (or any further upgrade) will fix all issues. See the http://archives.mandrivalinux.com/cooker/2005-07/msg01012.php thread for a more detailed explanation.