I received my first SMS spam yesterday, followed by 5 more. I noticed that they all were coming from aol so I tried the following.

Using TreoHelper (search for treohelper, userid potatoho) I configured a SMS filter to delete all SMS from aol.

Appears to be working.

Potatoho is hopefully working on a Treo600 version of "PBJTime", essentially a SMS folder to stick filtered SMS messeges in.

This would also solve the SMS-Popup issue some are reporting.