Custom Identify Results - need custom layer??

Hello,

I'd like to override the right hand side of the Identify Dialog with custom values for my shapefile layers. I really don't want to implement my own Identify dialog since I like the way Identify handles rubber banding to select multiple points at once.

I tried to make a "custom" layer by extending FeatureLayerClass and implementing IIdentifyObj. Unfortunately, my interface methods for IIdentifyObj were never called. The samples were implementing this for a dynamic base layer and I have a simple shapefile.

Can someone tell me what I'm doing wrong?

Thanks,
Mary