Unicode character - complex password policy in AD

I got complexity enabled for user passwords in AD (Password must meet complexity requirement is Enabled)

Per the Microsoft article, the password allows are:

http://technet.microsoft.com/en-us/library/cc786468(v=ws.10).aspx 

Any Unicode character that is categorized as an alphabetic character but is not uppercase or lowercase. This includes Unicode characters from Asian languages.

I have been asked to provide hint to user what characters are allowed under the tag line above (unicode characters, what unicode characters are allowed to be part of user password?)

Thanks

Inderjit