MTS GetOriginalCallerName

I have a three MTS components,
- one that have a function that gets the user name with GetObjectContext().Security.GetOriginalCallerName – let name it test.first with the function GetCaller
and two others that returns the usernames by calling the first one with the GetObjectContext().CreateInstance(”test.first”))->GetCaller, lets name this test1.second and test2.second whith the functions GetCallerFailure

When I create an object directly from an ASP page I always get the same correct result.
But when I call the function indirect I get the correct username sometimes and 'NT AUTHORITY\SYSTEM' sometimes?

The call stack locks like this when I debug the component:
Test.first.GetCaller
[<Non-Basic Code>]
test1.second1/2.GetCallerFailure

Question 1)
Is it anybody that have seen this problem before, and know how to fix it

Question 2)
Is it anybody that knows more precisely what the [<Non-Basic Code>] is and where i can find documentation about it?