Wont boot from complete battery rundown - Vaio E Series

On Sunday evening, while on a train I ran the battery down completely using my VPC-EB1Z0E. When I went to boot it up again yesterday morning, plugged into the mains, nothing happened. The orange 'charging' light on the front was lit, but pressing the power button did nothing. The power button light would 'throb' green as I held it down, and would pulse occassionally as I left it - almost lie the low battery signal you get when using it near empty.

I tried removing the battery and running it mains only. This did not work. I tried holding down the power button for a minute to discharge the power - both mains and on battery - this had no effect.

The best I can get is running it on battery, holding down the power button for a while, the fan kicks in after 10 seconds, but no other sign of life. The power then cuts out after another 5-10 seconds.

I left it charging it for eight hours. This had no effect.

I left it with the battery out overnight last night. This has had no effect.

Looking at what seemed like similar symptoms in a F11 fan problem I read of on here, I tried disconnecting the CMOS battery from the mobo for a minute or two. This also had no effect.

It feels like this is a hibernate/standby bug and shoule be fixable without having to fork out for an engineer. Any help gratefully received.

It's 19 months old and never shown any other problem.