Keyboard problem - extra keys pressed

[wolffit]

Phone: Verizon XV6800
Problem: When typing quickly, extra keys are sometimes enterred. In particular, when typing 'c' followed by 'o', if I start depressing the 'o' key before the 'c' is fully released, the phone puts a 'j' in between, so I wind up typing 'cjom' instead of 'com'. In order to avoid this problem I have to significantly slow down my typing speed.
As my phone is still within Verizon's 30 day satisfaction guarantee period, I replaced the phone - the new one has the same problem. People I know who have the same phone with Sprint do not have that problem. Is there a software/firmware update that fixes this? Has anyone else experienced this problem?

One simple way to reproduce the problem is to press 'c', then while holding 'c' down, press 'o'.