UDT as in parameter problem

[vinodp]

Hi,
I have a ATL outproc server. i am taking a UDT from a client as in parameter.
HRESULT test([in]SomeUDT);
but when my client is calling this method in VB its getting byval error.
if i changed this signature to
HRESULT test([in]SomeUDT*);
i.e to pointer its working fine.

can anybody tell me why i need to declare it as pointer to pass a UDT as in parameter from VB.

Vinod