I was just using the web browser on my replacement Blackberry Curve 8520 when the dreaded white screen returned. The only way out of this is to remove the battery. This forces a reboot each time. As the reboot finished the white screen reappeared. Having tried and failed 3 times I admitted defeat and have consigned the Blackberry to the scrap heap.
I rang Vodafone twice today to try and sort but didn't get very far. I also didn't realise it was this serious. I'm now without a mobile for phone and emails, probably until Wednesday at the earliest.