asp.net - Regexing an email with national chars -

i trying build web site friend of mine. found nice article contact-form. in article usage of regex validation of emails explained (as anti-hacking tool). idea tried this:

<asp:regularexpressionvalidator validationexpression="^([\w\-\.\+\~]+\@[\w\.\-\!]+)$" runat="server" controltovalidate="email" cssclass="text-danger" errormessage="invalid email." ></asp:regularexpressionvalidator> 

it works expected when gets usual emaile me@master.com. want allow national special chars ç or é, email sněhurka@trpaslíci.cz through.

the reason behind fact in country (czech republic) (was?) motion allow characters punctuation in url addresses (see http://háčkyčárky.cz - czech web discussing this; idea named idn - internationalized domain names - google-magic). far know didn´t got through, knows future holds?

so, please, know way how improve regex national characters in mind? (yeah, suppose not standard-compliant, not care it.)

i suppose can hand-write chars regex, seems nasty , ugly way. plus not allow chars e.g french, magyar, ... alphabet since not know them.

thank ideas,

rao