User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en) AppleWebKit/419.2.1 (KHTML, like Gecko) Safari/419.3 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.8.1.4) Gecko/20070515 Firefox/2.0.0.4 When a Web site requires client SSL authentication for access, and there is no client certificate in the firefox key store or only an expired certificate, a popup alert dialog is displayed with the error message "<web site url> has received an incorrect or unexpected message. Error Code: -12227". This error message should be changed to make it more user friendly. Reproducible: Always Steps to Reproduce: 1.Attempt to access Web server with client SSL required 2.Popup error message dialog is displayed. No Web site content is loaded. Actual Results: See Details. Expected Results: The popup error message should be more useful, e.g. "Unable to establish SSL connection. A client certificate is required." See Details.