This is what you should do-
If the player tells him a secret combination of words there (using the
easy chat system), he will give him or her a new wallpaper for their
PC boxes or a Pokémon Egg. Each combination differs from between games
and is dependent on the player's ID. The egg given can either hatch
into a Mareep, Wooper, or a Slugma.
generator- Bulbapedia
For more info go here-http://bulbapedia.bulbagarden.net/wiki/Primo
The combination is different for everyone (Unrecognizable)
Hope this helps =P