I gotta explain it :
First of all we need :
2 Chars : Lv 110+++* and Lv 502-3 Pets
Level must be over 50
Both chars go to the cave
With the High lvl char you going to use pet summon bug
1. Go to the Stone
2. Summon first the LOW LEVEL pet, than close and summon the High level pet
2. You should get Dc'ed, by server
3. Relog, you should have open 2 pets in inventory, maybe the low level is summoned
4. Exchange the high lvl pet to your low lvl char, and teleport with your low lvl char out of the cave ...
5. Have fun lvling
For the pro's :
Do the cave bug, give the high lvl pet to your other char and teleport