"Well, it turns out that StorageTek allegedly uses some kind of algorithmic "key" to control access to its "Maintenance Code", the module that allows the service tech to debug the storage system. The court found that third party service techs who used the key without StorageTek's permission "circumvented" to gain access to the copyrighted code in violation of the DMCA, even though they had the explicit permission of the purchasers to fix their machines. ...If you are interested, the Anti-DMCA Website looks like a good source of information.
The Court also found, in a bizarre twist of logic, that while it is legal to load a program into RAM for repairs, it's illegal to allow it to persist in RAM while you fix it."
Also, note that Creative Commons , the organization under whose copyright license this blog is protected, and the Electronic Frontier Foundation are additional good sources of information.