This is probably a long shot, but i'll try anyway.
I'm looking for RC4 (arcfour) encryption in Filemaker, exactly in the same way as you can see on this website: http://rc4.online-domain-tools.com/
Simply filling in a 'input text' and a 'key' and then generating the encrypted text.
-Input text: rylG
Result: fb a6 e4 78