use second or third class weapons
Can a persons first class toon use the second or third classes toons weapons?
Only if...
1. The compatibility of the classes is the same for the weapon (priests and mages can both use a 2-H Staff)
2. One of the classes has a skill that allows the use of a certain type of weapon (Scout general skill allows use of bows with x/S classes or Warrior general skill allows use of 1-H axes for x/W classes) Example would be R/W duel wielding 1-H axes.
3rd classes are basically ignored for everything so a K/S with a warrior third class can not use an axe but can use a bow, if you swap to K/W with scout third class you can use an axe but not a bow.
I believe the class descriptions on theromwiki says what weapons each class can use.