BB Curve :: Crashes During Reboot?

Basically, the phone went completely dead, despite being fully charged. At first there was no response from the phone whatsoever and this went on for about 4 hours. I was out of the house and had no charger so assumed that maybe the battery had run out.However, after about 4 hours the Blackberry began behaving very weirdly. Every so often, the red LED light comes on for about 10 seconds and then it tries to switch on (without me pressing a button). The reboot bar comes up, but when this is only about 5-10% full the Blackberry crashes and does exactly the same thing again, crashing at the same point. Sometimes it can do this continuously and sometimes it will go completely unresponsive again.

Removing the battery makes no difference, because when I put it back in it simply behaves in the same way.I tried launching a software update through BB Desktop to remedy this, but half-way through the programme said that it could not connect to the Blackberry, even though it had previously been connected.