EncodedNybble on 18 February 2010
I'll give more explanation here.
Games purchased on the PSN (currently this is how their DRM works) you can have up to 5 PS3s and 5 PSPs all "activated" on the same PSN ID. Any game bought from that PSN ID can be used on those systems as long as those systems are still activated under the purchasing PSN ID.
A PSP can only have 1 active PSN ID on it at a time.
Thus, if you, using your PSN ID on your PSP any game that is on the PSP that was downloaded via another PSN ID (and thus locked to that PSN ID) you cannot play unless your PSP is activated on that PSN ID.
