bagder/curl — pull request #39 by arnx (2012-07-21 10:54:30+00:00)
Title: HTTP digest auth "qop" param

RFC states what client's qop is:
message-qop = "qop" "=" qop-value
where:
qop-value = "auth" | "auth-int" | token
So, client's qop parameter must be single unquoted token.