Didn't see a thread for it so I decided to make one.
If the answer is Yes......
Is there a dedicated Lobby everyone plays in?
If it's no but you are interested...
This will show you how to set up JAP PSN account:
Once you have your Japanese account, To download adhoc party, sign into psn and go into the second option from the bottom[it should start with a star symbol and in the middle of the line of jap characters should be"PS3"]
ad hoc party icon is distinguishable by its green color with white print, along with white stick figures....adhoc party should be legible in the icon.
next connect you psp to your ps3 via usb. your wifi will be used for your psp
Run the program from your xmb and do the first option first to agree to the EULA. You'll get an error if you don't.
After this it was just trial and error for me but there is a tutorial here:
If there isn't a dedicated lobby for this game may i suggest we make one?
Lobby 50, though usually does contain people that speak english...its usually filled with people that play monster hunter, though you do get a few people play PS:P