My phone (pantech crux) has the same software version as you state above, and has the problem with double text messages.
It also forgets calendar reminders when the power is cycled. The screen sometimes flashes back off when unlocking the front cover. There are simply software issues since everyone is trying to make the new phone quckly instead of making the new phone correctly... and apparently not following up with software updates either.
I don't blame pantech, I blame the verizon base software. My last verizon phone also had calendar reminder issues, the alarms time gets updated at the same time the daylight savings time does (making you an hour off)... and I expect the same from this phone.
I got the phone new on 24JUL2011 (2mos old) and it's had these issues from day one - the last phone I had for ~3 years.