Serious formatting issues in forum

We're having serious issues for displaying text posted in the fora. The old module which converted the raw text to HTML is no longer available and we need to find an alternative. The old method used a 'wiki style' module which respected line breaks, converted links and formatted space indented text as fixed font text (like  would do).

There is currently no wiki filter installed which works in the same way. Mediawiki comes close, but does not respect line breaks and 'crashes' on the occurence of triple-{, Creole does not respect line breaks, and only the triple-{ fixed font text formatting. DokuWiki respects line breaks but not the fixed font formatting.

This is quite urgent as much old content used the old filter, especially content coming from the mailing lists.

 This line should be fixed width (like a code example)
  Same, but this line has two spaces should be a clickable link

these should
three lines

  // this is also a code example


Serious formatting issues in forum

I succeeded in 'porting' the old wiki filter to Drupal 5, the parent post is using the forum-for-mailhandler input type.