Name: I created a Rhul-Thaun (Athasian halfling variant) warlock character last week: Login name is Barley, Character Name is Bal-Wir of Sul
Where: everywhere
When: always
What: in the character creation area I purchased stone bolts (a unique crossbow bolt available at character creation for Athasian characters). Whenever the stone bolts are equipped my PC's damage is lowered -2 slashing with any weapon he wields (tested with dagger, spear, morningstar, and unarmed). And if wielding the heavy crossbow his damage is lowered by -2 slashing and -2 Piercing.
Recreate: Always, when stone bolts are equiped. Unequip the stone bolts and there are no damage deductions.