I have a project written in C#, which I then create a TLB from. In VC6
I import this .tlb which in turns generates a tlh file. Intellisense
gets it's information from this .thl file ( I tested it).

The only problem is that in the method declarations it always puts
pRetVal as the name of the arguments that set the properties in C#.
i.e:
void PutAbsolutePosition (DATE pRetVal );

Is there any way to change this so it will have a more meaningful name?

for example void PutAbsolutePosition (DATE position);
even PutAbsolutePosition (DATE value); would be fine

In my C# solution I also have a C++ project that implements this
interface and I changed the name of the arguments in that
implementation, but this doesn't change the original interface
declaration (in C# using properties) which in turn creates the TLB file
that everything is generated from.

Thanks