Key Points:

The American man jailed yesterday for hacking a University of Pennsylvania computer server "effectively hired" a New Zealand teenager to carry out an attack on internet chat groups, a prosecutor says.

Ryan Goldstein, 22, a student at the university, online offered Whitianga teenager Owen Thor Walker log-in rights to a website and malicious "trojan horse" software, Michael Levy, chief of computer crimes with the US Attorney's Office for the Eastern District of Pennsylvania.

In return Walker, known online as AKILL, agreed to train his botnet on Goldstein's targets.

"Did he pay him? It's in internet currency: 'Here's some tools for your kit bag,"' he said. "Did he send him money through this Paypal account? No."

Internet news website said today Goldstein wanted to wage an online war with three IRC (Internet Relay Chat) networks and a now-defunct website called,

He was angry after being banned from at least one of the forums, and he talked the 18 year-old New Zealander into launching a distributed denial-of-service attack against these networks.

Goldstein and Walker were arrested as part of the US Federal Bureau of Investigation's Operation Bot Roast II, and Goldstein was this week jailed for three months followed by probation time.

He will be on probation for five years,

He was also fined US$30,000 ($51,800) and must pay US$6100 in restitution to the university whose computer was attacked in February 2006.

Walker, 19, known online as AKILL, was discharged without conviction at the High Court in Hamilton last July after admitting six cyber crime charges.

Both crown lawyer Ross Douch and defence lawyer Tony Balme told the court that police were interested in using Walker's skills on the right side of the law.