Currently I'm developing/maintaining click redirection web servers that send 'Location:' header back to the users at the end of the process. But the problem is that it does not work with IDN urls(those having non-ascii characters such as asian characters) ONLY ON INTERNET EXPLORER 7.

I've found that IE6 simply trys to ask plug-ins or DNS servers to get the punycode(something like "") when received a Location header with IDN, which does not make any problems afterall. but IE7 fails to redirect. It seems that IE7 can handle IDN internally but do not use punycode translation when following 'Location' header with non-ascii characters. Actually it also happens on firefox(which supports IDN internally as well), the only difference being that this time it trys to url_encode the entire address, and then fails(so it tries an address like '').

Is this a bug of IE7, or am I wrongly using Location header with IDN It's becoming quite a serious problem but I cannot find any information anywhere. Any ideas