RIAA withdraws suit - Grandma not a thief after all

The Boston Globe carried an interesting article about the RIAA withdrawing one of the 261 suits it filed the other week. The piece includes this lovely and oh-so-informative snippet:

Evan Cox, a partner with Covington & Burling in San Francisco who is not involved with the case, said the error most likely happened in one of two ways: Either Comcast matched the wrong customer with the IP address, or the recording industry requested information about the wrong IP address, which is usually more than nine digits. "If any of those [IP address] numbers are wrong or transposed, you're going to get the wrong person," [the EFF's] Cohn said.

Nah, really? Do phone numbers work the same way?