We have developed a Mobile Media Center product, which uses a login page created in xhtml. It works on most mobile phones, but on some phones (not only Nokia) the "submit" button on the form doesn't seem to do anything (this is, it doesn't even try to load the url mentioned in the action parameter of the form, it seems like nothing is exectuted if the button is pressed). I've tried several things, like changing the method from get into post, using absolute and relative urls in the action parameter, etc, but no result.
More information and (free) download of the application at www.mobilemediacenter.nl (Click on Express version, download).
Please let me know which brand/type and provider you've used to login and let me know if login was succesfull or not.
Could a post to a .asp page be blocked by a provider ??