Access COM from CAT VBA

[seahorse_saps]

Hi All,

I am having problem accessing COM interfaces from VBA. I
have already used COM Automation interfaces created via
CAA. But now i wanted to access plain C++ COM interface
which i have created. I used the below code

sub catmain()
Dim obj as lib.Interface
Set obj = CreateObject("TCU.Objet")
Dim msg as string
On error resume next
obj.logout()
end sub

when i keep "." after obj, it can list down all the
methods i created in my idl. This above code should work
fine. but i am not sure where the mistake is. It says
"syntax error" for obj.logout(). when i try to run it. it
says "compilation error. Expected: =" for obj.logout().
can anyone advice me what is the issue?