Laptop won't shutdown when plugged in

[castletonia]

I just installed Ubuntu 10.10 64-bit on my Toshiba M305D-S4831 and all is fine except when I go to shutdown. If I am plugged in, my laptop will restart itself when I go to shutdown. When I am on battery power only, it will shutdown. The same issue also occurred using Mint 10. It did however work fine using Zorin 4 core. Any suggestions for a linux newbie?

[castletonia]

I just installed Ubuntu 10.10 64-bit on my Toshiba M305D-S4831 and all is fine except when I go to shutdown. If I am plugged in, my laptop will restart itself when I go to shutdown. When I am on battery power only, it will shutdown. The same issue also occurred using Mint 10. It did however work fine using Zorin 4 core. Any suggestions for a linux newbie?

Anyone?