First off welcome.
A couple things, as I understand still, this issue is an issue with android. It occasionally still happens to me but it occurs most often with longer texts as you mentioned and with an aggressive texting pattern (that is many back and forth texting with a particular person). It never happens to me with the occasional text here and there.
I would also like to mention that this site is for the Samsung Droid Charge and that's what we support. Please feel free to visit our sister site for more specific advice for the RAZR: Droid RAZR Forum