You can use a login form by embedding the user name and password into the submitted link. This can be done using the onsubmit action of the submit button to modify the link when the user clicks on it. The disadvantage is that the once the page is returned the username and password will appear in the user's typein location bar. This means it can be bookmarked. The workaround is to use an intermediate page meta-refresh with a delay of zero to the actual user viewable page. This will move the page fast enough that the user will not book mark it. A side effect of this technique is that the back button will not work because the user will be going back one page which then goes forward again. An additional consideration is the the user visible page cannot be in a protected area because the browser does not send referrer information on the meta-refresh request. A request to a protected area will fail on such a request because of the referrer check mechanism ...

As digest authentication is defined as a feature of the HTTP/1.1 protocol only those browsers will respond with MD5 digest user credentials. HTTP/1.0 browsers will respond with Base64 encoded user credentials.

Additionally, the browser must have HTTP/1.1 enabled in the user settings. Finally, if the user is passing through a proxy that is only capable of HTTP/1.0 then MD5 digest user credentials will not be used ...