Hiya, try this one: http://ecsi.chem.uva.nl/seq-fac/seq-fac.html Good luck, Rogier -- Rogier Stuger Dept MicFizz, Free U of A E rogier AT biogate DOT com (spammers will be killed) do NOT use the my-deja.com address. I never read that one Sent via Deja.com http://www.deja.com/ Before you buy.