As I mentioned before, how did you find out about it?

If your daughter is under 14 years of age then there is an obvious solution:

Eligibility. Use of and Membership in the MySpace Services is void where prohibited. By using the MySpace Services, you represent and warrant that (a) all registration information you submit is truthful and accurate; (b) you will maintain the accuracy of such information; (c) you are 14 years of age or older; and (d) your use of the MySpace Services does not violate any applicable law or regulation. Your profile may be deleted and your Membership may be terminated without warning, if we believe that you are under 14 years of age.
The addition of the name of a friend indicates that this is someone who knows both of them.

If you examine the MySpace site you will see that there are league tables for schools and the number of members they have signed up.

That makes me think that it is even more likely that it was someone at her school that did it. If that is the case then you are certainly looking at "mission impossible" as they would doubtless have used a school or Library computer.

It would be interesting to know if her friend has a MySpace account, and if they do, are they aware of it, and did they set it up themselves?

It would not be surprising to me to find that fellow students had done this to boost the school's "league rating"

Just a few thoughts