That's not the SMS app, that's the SIP you're using. Try finding a new keyboard, like http://www.pocketcm.com/keyboard2.php that doesn't include the "black bar" (suggestion bar)
i was thinking the same thing. i say try out a new kb and if the problem persist might be somthing else thats causing it. never really heard of the texting app being faulty, imho
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MoonZ~BabysH
SGT MoonZ, Reporting for Duty...CBM, Google Search & Rescue Division!!!