using vb 4/6 dll in c#

Question

Hi,
    I have a dll created in vb 4/6 (not sure whether it is created using vb 4 or vb 6, yet to confirm).  I want to use it in my c# 4.0 project. I have tried to register the dll using regsvr32.exe.  But I am getting the error "mydll.dll was loaded, but the dllRegisterServer entry point was not found.  This file can not be registered".  I searched through various forums but the suggestions didn't work.  Please help.

Cris Evan