Roboform Lite is compatible with Firefox 6.
https://addons.mozilla.org/en-US/firefox/addon/roboform-online-password-manag/

The problem is with Firefox 5 not 6. I didn't even know there was a 6.0 version yet.

Yes but only from the latest version (7.3.2 ) For the earlier versions you can only use RoboForm from the taskbar so you don't have the toolbar and the possibility to right-click and select Fill Forms.

Hope I helped you :)

Mirkom, I thank you very much. I do have version 7.3.2.

I have Roboform 7.3.0 and am using firefox 4.01 . I have the taskbar icon and at upper left corner, 2 little arrows ( >> ). when you click on them you get an option selection similar to what you get from the taskbar icon. It doesn't let me autosave. When Firefox 4 was not compatible with my old version of Roboform, I dutifully bent over...........So Roboform could extract my wallet. I'm not happy because I have to click on the little arrows and they want to go away if I don't do it just right. I thought my money would buy me the regular toolbar :( . This just feels abusive. I surrender and they still only sort of deliver. That sucks.

Does Roboform 6 work any better with Roboform 7.3.0 ?

Oh, I forgot to say that I am using Roboform Portable.

Actually for Firefox 5 you can use this procedure posted by MeOminG regarding this issue for Firefox 4. Just substitute Roboform 7.3.2 where he refers to version 7.2.7, as you need at least this adapter version so that Firefox 5 accepts the adapter as being compatible.

actually there is a workaround. all credits to swmyp from ru -board

   Install Roboform 7.2.7
   Copy folder "c:\Program Files\Siber Systems\AI RoboForm\Firefox\"
   Install Roboform 6.10.2 -dont untick option to install adapter for firefox
   Replace "c:\Program Files\Siber Systems\AI RoboForm\Firefox\" with your copy from 7.2.7 version 

now u should have working 6.10.2 roboform with latest adapter from 7.2.7

If toolbar didnt appear right away after restart, remove Roboform toolbar extention from add-ons.

And likewise, for Firefox 6 you can also use this same procedure as long as you install the Roboform adapter that is compatible with Firefox 6- and that happens to be at least Roboform 7.4.1.

Actually for Firefox 5 you can use this procedure posted by MeOminG regarding this issue for Firefox 4. Just substitute Roboform 7.3.2 where he refers to version 7.2.7, as you need at least this adapter version so that Firefox 5 accepts the adapter as being compatible.

actually there is a workaround. all credits to swmyp from ru -board

  Install Roboform 7.2.7
  Copy folder "c:\Program Files\Siber Systems\AI RoboForm\Firefox\"
  Install Roboform 6.10.2 -dont untick option to install adapter for firefox
  Replace "c:\Program Files\Siber Systems\AI RoboForm\Firefox\" with your copy from 7.2.7 version 

now u should have working 6.10.2 roboform with latest adapter from 7.2.7

If toolbar didnt appear right away after restart, remove Roboform toolbar extention from add-ons.