Thank you for your reply thecreator. However, the ip phone is not USB, it connects to one of the ports of the router. I have installed 1.21 with and without the sharepoint but had to rollback to 1.11 because of reliability issues.
In addition to the Port Access Control problem, one of my workstations is showing authentication failed in the network icon in the status bar. I wonder if this is related to the Port Access Control?