C# with reference not working but VB.net is?

HI
Can anybody tell me why this VB.net script works:

Script:
Public Sub Main(Parms As String)
hs.WriteLog("Tester", "MainCalled")
Call GaitHs3Library.CallTest.TestCall(hs)
End Sub

but this C# script does not:
Script:
public Object Main(string parm)
{
hs.WriteLog("Tester", "Main Called");
GaitHs3Library.CallTest.TestCall(hs);
return null;
}


The C# script claims there is a compiler error with GaitHs3Library. And the ScriptingReferences file must be correct since the vb script works :-/


And ideas. Am i missing something in regard to the C#/cs script?