[ver2007] very strange error on macro execution

I'mworking on some macro.

Call of macro works properly...then I inserted a new function...

Function myFunction(pj As MSProject) As Boolean
...
End Function

I take this error when I try to lunch some (anyone) macro...

If I change input parameter of that function :

Function myFunction(pj As MSProject.Project) As Boolean
...
End Function

Why???

With empty code.

Thank you