When a Crowd User Directory is set up to have a password regex and then linked to Confluence, no feedback is given at all when attempting to create a new user via email invitation or via self-signup, and if you attempt to change an existing users password to something that doesn't meet the regex you are given a stacktrace.

Steps to Reproduce:

1. Configure a Crowd directory to have a password regex (under the configuration tab)
2. Set up Confluence to have this Crowd directory at the top of your directories list, so users are added to this directory upon creation
3. Allow for self-signup or email a user invitation
4. Note that if you attempt to create an account which fails the password regex, absolutely no feedback is given. An error is shown in the logs, however.
5. Alternatively, create a user with a valid password, then attempt to change that password for the user. This will result in the following:
   

Notes:

1. If you attempt to add a user via 'Add a User', you are given an error message (which reads 'The following error(s) occurred: Failed to create the user 'disabler'. Check your server logs for more information.')
2. If the user changes their own password, they are shown the following error message: 'The new password you entered is invalid.'