Maybe contact GoDaddy. Is it possible you are past your limit for the day? I can't seem to find any problems with your script and I've tried several others without success. Emails are not sending, but I don't think it is a problem with the php code.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.