[OpenIndiana-discuss] urgent help please

[hugo.heykers at telenet.be]

I cannot boot any longer into the OS because of the error that "no space left on device" 
I have OpenIndiana installed as a guest virtualbox machine. 
I can only log in as root for system maintenance. 
I use this OS mainly for my mail communication, and therefore I've been shut out of it!! 
This is what I got: 
Please help me out, since I don't have any experience with this OS nor with opensolaris. 
My host OS is Ubuntu. 
Is there any way I can copy my mail directory? 
I use Thunderbird as mail client in OpenIndiana! 

Regards, 
Hugo Heykers - Belgium