I found the Wounding ability very cheap for what it does, especially at high levels. The following is what we use in our campaign.
Wounding: This replaces the property listed in the DMG v3.5, on page 226. A wounding weapon deals 1 point of temporary Constitution damage on every attack roll that is over the target’s AC by at least 5. If your target is wearing a heavy armor or has natural armor bonus of at least +10, then your attack needs to bypass the target’s armor by at least 10 in order to deal the Con damage. You can not deal this Con damage if your target is immune to criticals such as from fortification or natural immunity. You can not deal both bleeding* and wounding effect at the same time, because they are essentially similar damage: you have to choose which effect will takes place every round. A wounding property may only be added to a piercing or slashing melee weapon.
*another weapon property in our campaign
Wounding: This replaces the property listed in the DMG v3.5, on page 226. A wounding weapon deals 1 point of temporary Constitution damage on every attack roll that is over the target’s AC by at least 5. If your target is wearing a heavy armor or has natural armor bonus of at least +10, then your attack needs to bypass the target’s armor by at least 10 in order to deal the Con damage. You can not deal this Con damage if your target is immune to criticals such as from fortification or natural immunity. You can not deal both bleeding* and wounding effect at the same time, because they are essentially similar damage: you have to choose which effect will takes place every round. A wounding property may only be added to a piercing or slashing melee weapon.
*another weapon property in our campaign