Netscape mail help

I'm trying to create message filters in Netscape mail, but for some reason, for my primary domain account, it won't allow me to do it.

I got to Edit -> Message Filters and then select the account. I then click on "new" to create the filter rule, but nothing happens. However, when I do the same thing with seemag1@yahoo.com, the approriate dialog box pops up and allows me to make a rule.

Anyone have any ideas on what's going on?