It seems happy with an array of one key/value pair there, actually. I've updated my earlier post and hope I have better framed an answerable question. Earlier I was dealing with multiple frustrations. I'd love to get WWW::Mechanize::Shell working, but unless that's a give-away, that's tangential to my real goal right now, which is to work out this authentication issue. Thanks for your help on this though. I appreciate the additional eyes on my code.