Try to do a verifyUser (method of the ARServerUser Class) to confirm that you have made a successful connection. Sometime you can "connect" but you are not really connected/logged in.
Also, check that you can submit into that form. If all this works and you still can't use it, then it seems your qualification is incorrect.
Have you consider trying Web Services instead? Makes life easier when you need to change something. (No recompiling required)
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Mayhem, Chaos and Anarchy
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