I've been using the Thanks feature since 2011 and never had an issue. Maybe it is browser related?
I've tried (On Windows) FireFox, Opera, Chrome and IE and I also have tried on these browsers - Dolphin and Chrome on the following devices, Galaxy S4, HTC EVO 3D, Nexus 7 and Galaxy Tab 2.
If you're using one of those mentioned browsers and no dice ... I'd have to assume your host is disagreeing with the javascript code somehow.