Several weeks ago at http://twitter.com/martinog, I twittered:
"At times my iPhone 3GS does not make outgoing phone calls until I power on and off. Is it Sofware, Hardware or AT&T? #iphone #att #apple9:15 PM Sep 19th from Tweetie"
This bug is also known as iPhone Coma Mode. According to Apple, iPhone 3.1.2 should address this bug.
I am now installing this Apple iPhone 3.1.2 release. It offers bug fixes, but no flashy new features. You can get it now by plugging in your iPhone and clicking "Check for Updates" in iTunes. Here's Apple's list of what's fixed in this update:
* iPhone Sleep bug - Resolves sporadic issue that may cause iPhone not to wake from sleep
* iPhone Coma Mode bug - Resolves intermittent issue that may interrupt cellular services until restart
* iPhone Video Stream bug - Fixes bug that could cause occasional crash during video stream
The update is 306.2 MBs. It took less than 15 minutes to download on a Mac and about 35+ minutes on a PC.