Simple Weapon Proficiency
From Compendium of Worldly Lore
Needs review
Source: Player's Handbook
Description: You understand how to use all types of simple weapons in combat.
Prerequisites:
You make attack rolls with simple weapons normally.
Special
All characters except for druids, monks, rogues, and wizards (and any other class not noted as having simple weapon proficiency) are automatically proficient with all simple weapons. They need not select this feat. A sorcerer or wizard who casts the spell Tenser's Transformation on himself or herself gains proficiency with all simple weapons for the duration of the spell.
Normal
When using a weapon with which you are not proficient, you take a -4 penalty on attack rolls.