I've just upgraded to 1.3.1 (using official Palm update) my unlocked O2 German Pre. I haven't noticed any problem with upgrade.
During upgrade I didn't have SIM card inserted and I immediately changed manual network settings. I got "invalid APN settings" message , but I chose "Setup anyway".
I did shut-down, removed battery, inserted SIM and rebooted.
No data. I checked network settings, I needed to turn-on again manual setting and enter all changes again (APN...).
This time I got again "invalid APN settings" message , but after I chose "Setup anyway". I got Unable to write settings
Reset didn't help.
I didn't try db hack earlier, neither installed Sprint/Bell firmware. I am running of ideas ?