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http://devpro.it/code/44.html
* class md5 - AS2.0 - porting from original Paul Johnston JavaScript functions
* This is just a porting from Paul Johnston's JavaScript md5 implementation.
* Porting created by Andrea Giammarchi [ andr3a ] [
www.3site.it ] on 05/07/2004
*
* Version 1.0 Copyright (C) Andrea Giammarchi 2004