What would cause water to collect beneath the crispers of my refrigerator-freezer?

[yahoo]

This electrolux frigidaire has the freezer on top w/icemaker.  It is a frost proof model # FRT21LR7AW1, servicemen looked at this but could not tell me what was causing the problem.
I know it is not a condensation or a drip-pan problem..

[TechnicianBrian]

The most likely answer is the drain below the evaporator coils behind the freezer bad wall is blocked and everytime the unit goes into defrost, the water runs down the air passageways to the refrigerator instead of the drain and ends up at the bottom of the refer.  Removing the freezer rear panel will most likely reveal the problem.

[JWWebster]

probably a small piece of freezer paper blocking the drainhole under the coils.