Setting numeric attribute value to null

JesseAdams

I'm working on an editing application where I need to allow the user to set a numeric attribute field to null through an attribute inspector.  So far setting multiple text fields to "" works without any issues however when I try to set the field value to null using the following code it doesn't stick.

featureIn.attributes[fieldName] = null;

Currently I have this code in the "onAttributeChange" event.  This works with any number but not "null".  Any suggestions?  Thank you!