Drupal 6?

I had this ready a while ago, but an issue with my file system caused it to disappear from the module page, and a chase for a nonexistent bug ensued.

In addition to the patch, you should create a new file called "session_limit.install" that contains

<?php

/**
 * @file session_limit.install
 * Contains install and update functions for Session Limit.
 *
 * @ingroup session_limit
 */

function session_limit_uninstall() {
  variable_del('session_limit_max');
}

As you can see in the patch, there are still a few changes I would like to make to it.
Also, I am still fairly new at drupal and php in general, so there might be some issues.

Even so, I am willing to maintain this module if the current dev is no longer working on it.

Any more word on the v6 version please? This is exactly what I need for a new implementation...

Unfortunately, several users of my site were having issues with this, and I never got around to resolving them. You can try to use it, but be forwarned.