Gnucash dies when opening my data file

[Jon Loose]

I've just completed my first year using gnucash for home accounts, and it's been excellent on the whole.  System is xubuntu (with gnome in addition to xfce), gnucash is 2.2.6 (from ubuntu repos).  

It seems that my system didn't go down cleanly last night, as there is a lock file remaining.  When opening gnucash today, I'm asked what to do about the lock file.  I say 'ignore' and the dialog disappears, but then gnucash just dies - so I have no way of getting to my data.

Any thoughts much appreciated.  I hope I haven't just lost a year's information.

Jon