Using VB 6.0 Variant in ASP.NET

 Hi Alls,
I am using ASP.NET 2.0
I am using a dll which was written in VB 6.0 I want to use a function which uses one parameter as variant 
Optional ByRef FirstNames As Variant, _
If I use string or any other type, it give Type Mismatch error.
Any one have any idea Plz.
 
...