"Untriaged" to "Undecided" rename broke search form URLs

The 2006-09-26 rollout of Malone broke backwards compatibility with its search form. Old queries scattered over the Internet (like the Ubuntu wiki) no longer work.

For instance, a query for untriaged bugs such as:
https://launchpad.net/distros/ubuntu/+bugs?orderby=-importance&search=Search&field.searchtext=&assignee_option=none&field.omit_dupes=on&field.omit_dupes.used=&field.has_patch.used=&field.has_no_package.used=&field.component=1&field.component=6&field.component=2&field.status=Unconfirmed&field.owner=&field.importance=Untriaged&field.component-empty-marker=1&field.assignee=
returns an "Error: Unexpected form data".

It looks like this breakage occurred when we changed the Importance value of "Untriaged" to "Undecided".

It's pretty bad form to break links as there's no good way to hunt them down and fix them. Please add support for the old parameters names as aliases to any new ones, or at the very least, drop deprecated names gracefully.

Thanks!