It appears that when students enter a password containing one or more '$' characters, when submitting via the Eclipse Electronic Submission plug-in, that authentication does not occur. We are now using LDAP, but encountered the same issue in previous semesters when Web-CAT generated its own passwords. When submitting no response is received from Web-CAT - not even an error message indicating that the password was incorrect.
Tony, this sounds like some kind of encoding issue when the credentials are fowarded as part of the HTTP request for making the submission. Can you take a look? Note that you may be able to recreate it on your development machine using a database-authenticated account with an appropriate password. You can log parameters coming into Web-CAT as part of the submission request to get more visibility of the failure if needed.