AMF vs. Polymorphed/Shapechanged wizard

[Grog]

Say a wizard is shapechanged into a Huge (15' x 15') or larger creature, and someone with an AMF (10' radius centered on caster) walks right up next to him. What would happen? Would the spell be negated? How much of the wizard's body would have to be inside the AMF for that to happen?

I tend to think the answer would have to be something other than "any part at all", because then you could have a situation where a shapechanged wizard reaches inside an AMF with one finger, then the spell is instantly negated and the wizard is standing 20' away with no part of his body inside the AMF, so the spell is instantly resumed, etc.

 

[Ferox4]

from the SRD:

Should a creature be larger than the area enclosed by the barrier, any part of it that lies outside the barrier is unaffected by the field.

So essentially, if your huge shapechanged wizard tries a melee attack against the cleric inside his AMF I believe it would appear as if its fist, tentacle, or what have you simply disappeared as it passes into the AMF. The rest of "you" that remains outside would remain shapechanged. The AMF essentially "peels" away the spell as you move closer to its source.

Now what if you're wielding an huge sword (nomagically huge)? Do you think that since the magical effect that allows you to wield it is now supressed you drop the sword at the moment your hand enters the AMF?