iPhoto comments help

Hi

I'm slowly going through my photo library and adding comments to the photos to try and organise things. One thing I would like to be able to do is create a smart folder to contain all photos that are uncommented. The various options such as "contains", "is", "is not" etc don't cover it, unless there's some way of specifying wildcards that I've not found yet. I was going to try "does not contain a" & "does not contain b" & "does not contain c" etc as a workaround, but it would only let me get up to j and wouldn't let me enter any more conditions.

Any ideas how to do this?

Cheers

yod9999

 

anyone?