I too would be interested in this.
For anyone who doesn't know what the topic is talking about, Devil Survivor 2: Record Breaker (a remake of the original DS2) had three characters from Durarara!! available for download. I think this was all via the spotpass function. Alas, these characters don't seem to be on the docket for the US release due to licensing issues, so we're left with needing to hack this stuff in.
Unfortunately, I am very ignorant when it comes to spotpass type stuff. Is this simply unlocking content already on the cart, or is it injecting fresh content? If it's the latter, can we inject whatever, or are there limitations?