White screen persists after restore
I just had my iPhone screen replaced, and it appears to be entirely functional. The apple logo is displayed upon bootup, and initially I was able to write a text message, so touch input should be OK too. However, after updating the firmware as suggested by iTunes, the iPhone freezes in a "white screen of death" ("wsod"). Before that, flickering lines are observed. When this occurs, the only option appears to be restarting by hold home+sleep for 10 seconds.
iTunes does not recognize the unit, unless it is turned on in restore mode (having the iPhone turned off, holding Home, inserting the USB connector, continuing to hold Home until the iTunes logo is displayed.) In restore mode, it can be reset to factory settings and updated through iTunes, but the white screen problem persists even after the update.
This iPhone is not jail-broken, but has had a 3rd party replace the screen. However, as explained the screen seems to be working, and I believe that I'm dealing with a software problem. Does anyone have any ideas?
iPhone 3G, Mac OS X (10.6.3), 16GB