Comment 26 for bug 82086

Also, digest authentication scheme has a lot of options, urllib doesn't implement them all, for two main reasons:
- lack of time
- digest aimed at providing better security than basic scheme, but can't, by design, compare with https (and if you use https, digest offers no additional security anymore so using basic + https is the preferred way).

That being said, using -Dhttp option in your commands will provide enough information to confirm to diagnose such missing options in the digest implementation.