Windows 2003 VPN Filters & MSSQL

I've setup a VPN on a windows 2003 server. I would like mssql traffic to be allowed. I've setup a filter to allow all traffic orginating from any port to a destination port of 1433. I've also allowed all outgoing packets. But I still can't make a connection from another server via port 1433 (from php as an example). I've been able to successfully setup filters for all other services on the server like filemaker pro, file sharing, IIS, etc but mssql still escapes me. What other filters do I need to setup to allow mssql connections? Thanks