when IIS6 asks for WWW-Authenticate: Digest, DigestAuthentication cannot go thru and fails.

the reason is that in DigestAuthentication.getHeaderValueImpl(), when the Authorization header is generated, some fields are not quoted properly (like, auth=md5", the left quotation mark is missing). while apache can deal with this nicely, IIS6 will fail.

###@###.### 2005-03-02 06:51:50 GMT
###@###.### 2005-03-03 03:10:52 GMT