Making sense of codes for Stucco veneers over wood sheathing and Stick on Stone over wood sheathing

The current IRC2006 code for building paper below Pennsylvania & New Jersey

2006 IRC Code

Exterior Covering Section 703.

Exterior Plaster section Section 703.6

  703.6.3 Water Resistant Barriers.  Water- resistant barriers shall be installed as required in section R703.2 and where applied over wood based sheathing, shall include a water resistive vapor-permeable barrier with a performance at least equivalent to two layers of Grade D paper

Exception:  Where the water resistive barrier that is applied over wood based sheathing has a water resistance equal to or greater than that of 60 minute Grade D paper and is separated from the stucco by an intervening, substantially non watering-absorbing layer or designed drainage space.