thanks.
I used SimplyVBUnit, VBUnit and tools from AutomatedQA:
SimplyVBUnit (http://sourceforge.net/projects/simplyvbunit/):
It's free and there was a plug-in available anywhere (I'm sure).
VBUnit (http://www.vbunit.com):
Is not free anymore, but you can find earlier versions for free (try
google). Or you can buy the commercial version.
AutomatedQA TestComplete etc. (http://www.automatedqa.com):
Not free, not cheap, but very powerfull. You can do any test you like (unit,
load, web, interface ...) and you have access to the controls of your
application at runtime. It's a test suite where you write unit test in
ActiveX-exes and call the functionality of the test suite from within the
ActiveX. But unit-testing is only a very small part of the test suite. They
also provide AutomatedBuildStudio which integrates the tests into an
automated build. This is the most powerfull solution, but you need time to
learn it and some money to buy it.