Is Var Valid in an Extern block?

It seems to compile and work ok, but I'd like to know if that's intentional or just a happy mishap which might break or be changed.

Example :

Extern "Win32"
   Function QueryPerformanceCounter(count:Long Var)
End Extern

VS

Extern
   Function QueryPerformanceCounter(count:Long Ptr)
End Extern

Function _QueryPerformanceCounter(count:Long Var)
   QueryPerformanceCounter(VarPtr(count))
End Function

The first way is much cleaner, but I don't mind doing the second way if it's the preferred method. I'd just like to be sure which way *is* the preferred method though.