Just popped out to give that a go, still no luck. The rear buttons are jammed tight!
Thanks for your suggestions.
Just hope the garage solution isn't too costly!
Had exacly the same problem mate had to pull the inside cover off the rear door and used a drill ,hammer and big screw driver to smash the plastic and metal casing surrounding the lock and took three hours to do it,got another one from scrap yard for 20 quid and fitted it in 10 minutes.