Does a bag of holding bypass the effect of Wards?

Question

A necromancer has a bag of holding filled with his undead minions. Can he still cross through an Undeath Ward? My initial instinct is that the undead are not "crossing" the barrier because they are in an extradimensional space, disconnected from any effects on the material plane. However, I have not been able to find any official ruling on the impact of wards on extradimensional spaces.

Are there official rulings on the interplay between wards and extradimensional spaces?

What would happen if the bag were opened inside the Undeath Ward?

Answer 1

Most likely they could be brought in the Bag, but would not be able to exit the extradimensional space; it's unclear what would happen if the bag was turned inside-out.

They would not be able to simply exit the bag because, although they do not pass through the Ward's wall when brought in the Bag (they're not on the same plane*, so effects don't do anything to them unless otherwise stated), they would still be attempting to enter the spell's Area:

Area 10-ft.-radius emanation, centered on you

Mindless undead and intelligent undead with fewer Hit Dice than your caster level cannot enter the area or penetrate the barrier.

*This is because the range to them is undefined unless an effect transverses the Planes; as you can see in the "How Planes Interact" section, it is possible for effects to travel between planes, but only at appropriate places (such as the opening of a Bag of Holding).