Just ran into a situation today where I went into Desktop -> Settings -> About Phone -> System Updates -> Update Firmware
I think I hit some button while it was checking for updates, but it finished and just said no updates available. Well, I get back to the desktop and short push the power button to lock the phone and bam, nothing happens. I try a long push and the phone options come up. I go into camera and short push and a lock symbol still works. I long push and restart the phone, and the problem still persists. I just ran the Update Firmware process again and it seemed to fix the problem.
I had the same problem last night. I went to settings > about phone > system updates > update firmware. Hoping in vain to find the froyo update. The phone locked up during the update check. I had to take the battery out. When I rebooted a soft push on the power button would not blank the screen. I read the post below and tried to update firmware again. This time no lockup and when the phone reported that there was no update and I backed out to the home screen the soft push to blank screen feature worked again.
Specs: Stock Samsung Epic
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