Hypersmurf
Moderatarrrrh...
Now... What if the permanent spell is a higher caster level than the Permanency spell, and therefore gets dispelled first? There's an odd arrangement. With a duration of Permanent, the Permanency spell would continue on without a spell to make permanent. Though this may seem odd and useless at first, it could actually act as a defence against having "buffing" spell dispelled, so long as the "buffing" spell was cast at a lower caster level than the Permanency spell.
Well...
If you cast Greater Magic Weapon on a sword, and then someone Disintegrates the sword, would you say that the dust that remains would be GMWd still? Or, since the dust is not a weapon and therefore an invalid target for GMW, would the spell end?
I would think that if the original spell is dispelled, then Permanency no longer has a valid target, and fails.
-Hyp.