Noticed also yesterday my Sheeva blinking the green LED.
I open today the box and measured the power output supply voltage 2.5Vdc. Later open the power metal box and precisely identical failure as other, brown goo was everywhere in power supply. That power supply quality is totally crap
Anyway, I have one old mobile phone charger where output is rated to 5Vdc/2A. Size is almost same than original, so that fit's the original location.