String from Visual Basic to BP

I am trying to pass a string from a Visual Basic Application to a DLL written in BP
7.  Matching the data types is the problem.  Here's what I've tried...

1. ByVal String in VB (null terminated) to PChar in BP (pointer) - incompatible
types!
2. String in VB (32-bit pointer) to PChar in BP (far pointer) - thought this would
work but didn't.
3. ByVal String in VB (null terminated) to String in BP - different string lengths
and types!

Any help will be appreciated...