So I've been so happy with 4.2.1, none of the nightmares I went through with 4.1. It seems that may have been too early to celebrate? I'll have to wait and see

I have an iPhone 4, it's never been jailbroken since it was bought.
This morning I'm listening to music and I get a text message. The tone stops halfway through ringing and the music stops I look at my phone and it is showing the apple logo, it rebooted. It wasn't a full reboot though because it only took about 3 seconds after I looked at the screen that I was back at the lockscreen.
Then I got another text message, I go to type an poof no keyboard lol, I tried in both orientations and even exited the messages app and went back in. The keyboard didn't come up until I exited the message and went back in to it. I'm using the new tones so maybe something funky going on there? I did a reboot and I will see if anything happens again.
