Hello Customer (name blocked for privacy),
Welcome to Just Answer! According to AltaVista's Babel Fish Translator, Happy Birthday becomes "Ευτυχ? γεν?θλια" when translated to Greek.
You can see the results
here.I would also like to add, From the University of Missouri, a Greek major would say, literally, "Natalis laetus mihi!" or "Natalis laetus tibi!" depending on whether the greeting is to yourself or another. Thank you much to CivlDX for the assist and for providing this additional information.
Please let me know if I can be of further assistance.
Edited by Michele on January 11 2008 at 9:32 PM
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