make more login module form virtuemart for different members of the site

[lingue4ragazzero]

hello all,
i have this problem:
i would like make more different module form login  where evry module get an only kind of shopper group.
So i wil have in my database more group of shopper with different characteristics .
How i can get a different module form to do it in virtuemart?
it is possible get it with old version of joomla and virtuemart? there is some extension that let me have different module of subscription?
i can built a new site if it is necessary with joomla  1.7 or 2.5 and useing virtuemart 1.X or 2.x
thank you