Moving users from hikashop on J1.5.26 to J3.2.3

I've exported all the Hikashop tables from an installation on 1.5.26, which I used to import from osCommerce into Virtuemart, then to Hikashop. Then I exported all the Hikashop table and imported them into Joomla 3.2.3. The users are now all listed under Hikashop Customers but they are not in the Joomla user database, so some crucial information is missing, like name and username. Any ideas on how to fix this?

Thanks in advance...

OK, I see that I can use JUpgrade Pro.