If the IP address that it's coming from doesn't change, you can add an ACL to the Firewall denying all traffic from that address range.

Do you have access to the SpeedStream? Are there any errors that it's taking? It's a long shot, but have you replaced the 501 with another 501? What version of code on the 501 are you running at?

I currently have the exact scenario for about 40 remote sites. All running DSL/501 to a 3005. What type of DSL router are you using? I would check the router to see if you have any errors on the interface. Also check your DSL error rates as well....

There are very few CE based VPN clients, I have found Movian to be the most stable and easily configurable options on the market. Funk software has a CE client, however, its support of newer PDA devices is lacking.HTH

Check out the following link:http://www.cisco.com/en/US/products/sw/secursw/ps2120/products_command_reference_chapter09186a00801727ab.htmlGives an explanation of the commandHTH