we had the problem back in Aug, so I called and they walked me through the process of blocking text msgs from "online" sources. AOL, AIM, etc.
It worked fine for awhile, but the ones he got were all from AOL or AIM (in Nov). So I'm wondering if it reset itself or something.
They credited our account for the charges (not really that much, but I'm not paying for it!), and gave us some text credits to text them back to say not to "text us again" and if they do, to call and they can report them for harassment, or something like that.