Due to Haxe wiki limitation code had to be moved to pastebin: http://pastebin.com/s0VccheL
Haxe 3 port can be found here: https://github.com/as3boyan/tarwins_as3_to_haxe_conversion_script_-_haxe_neko_-

It can be compiled with the following compile.hxml

-main As3ToHaxe 
-neko bin\As3ToHaxe.n

It's still work in progress so developer notes:

• changes any 4x spaces to tabs (needed for later cleanup)
• fixes package, opening and closing braces as well
• fixes classes to be haxe-like
• replaces all the void, Boolean, Number, including
• fixes Vectors and adds imports
• fixes arrays, adding <Dynamic> (don't think there's an easy way to actually define these properly
• fixes protected and internet defs
• makes all namespaces private and adds a "using" for a friend class
• fixes "const" and creates static inline vars
• fixes Error class (simply imports flash.Error if it's used)
• creates proper haxe getter/setters

• TODO: create "friend" class from namespaces info collected information
• TODO: move initial var setting from var definition to constructor (not for static inline of course)
• TODO: loops.

If you have improvements please send them to the Haxe list for verification or post them on the Haxe forum.