however due to the existence of a previous mod by Hendrik Lipka, a mere version string edit is possible to make this addon functional again.
Unfortunately, that only results in a partially-working extension. It works for some forms, but is broken on many others. If you look at STT's code, you'll see that it's extremely fragile; it hooks itself into Firefox by literally re-writing built-in handler functions (see the gratuitous use of eval in the source), and that's just too fragile and buggy of an approach.
I've done a complete from-the-ground-up rewrite of STT. Works in Firefox 3 and newer and SeaMonkey 2 and newer. In Firefox 4 and SeaMonkey 2.1, it takes advantage of the new bootstrapping mechanisms so that it can be installed and uninstalled without restarting the browser. Oh, and it works more reliably than the old STT. http://code.kliu.org/misc/tabsubmit/https://addons.mozil...org/addon/tabsubmit/
You do have to uninstall STT if you install TabSubmit (it won't automatically overwrite STT because it has a different extension ID).