Hi Al,
I don't see anything about the system variables in the manual either but I don't think it's that big of a problem. If you're trying to declare T2 (or whatever) in your program but the compiler also declares T2 as it needs it for its library calls you'll get an error saying Redefinition of VAR - which I guess is the error Tobias got when he was using T1. So, it shouldn't cause any real trouble.
/Henrik.
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