Repeat: how do I erase mistakes from ~/.idata?

I posted the following here a couple days ago but got no replies.  I'm
hoping everyone simply thought, "Oh, that.  Fred will reply."  Only Fred's
mail server is down.  Anyone out there have any suggestions?

    I just hosed up an Emacs macro I was using to "learn" about particular
    messages and wound up with a bunch of bogus categories in my ~/.idata
    file.  Is there a way to tell ifile to delete a category and associated
    values from ~/.idata?

Thx,

-- 
Skip Montanaro - [email protected]
The need for gutters to be cleaned is directly proportional to how hard it
happens to be raining at the moment.