Can't explicitly unset a field in Integrator

I have an integration component where I call a scripted operation containing just one step of custom code, and then map the output of this operation to the fields in an output document. In my custom code I explicitly unset a certain field like this: out.$fieldname = false, but in the published document this field goes set, not unset.

I can�t figure out what�s the problem, I have the �allow unset fields� option checked in all my scripts.

I strongly suspect this is a bug, can you help me on this?

I�m using webMethods 4.1.1, running the Enterprise Integrator on my NT machine and the broker on a Solaris host running SunOS 5.6.

Thanks in advance,
CG

Just an update on this: I’ve tried to put my custom code step directly inside my Integration Component, and not inside a common scripted operation, which is then called from my IC, and surprisingly it seems to work fine.

Although this is a possible solution it’s not feasible for my case because I deal with tens of fields in this custom code block and I use it many times in this (and other) Integration Components. So I really want this code to be in a custom operation.

Once more thanks in advance for any help on this,
CG