Corrected entry: The ip addresses that the hackers would obtain when running their traces are internal network ip addresses. They look like 10.XXX.XXX.XXX or 172.XXX.XXX.XXX. They should have gotten the external ip address of the router or the firewall to that network. Also, it is very difficult to get a name associated with an ip address, especially if the ip address is for residential Internet usage because isps use dynamic ip addressing instead of static ip addressing. This means that the ip address of a customer will change every so often.
aheintz
12th Jul 2007
Correction: Most ISP's do offer a static IP address for an additional fee. Also they could have installed a backdoor to have when they need to terminate the hacker.
aheintz