Sanguinololu firmware upgrade issues

Hi all

My 2011 Sanguinololu 1.3a needs new firmware. It arrived with bootloader set to 38400 baud.

Initially I used Arduino 0023 on windows to load sprinter, this had no problems. However that PC died.

Now I have Linux Mint 17, and Arduino 1.0.5 (from software center). I found the Google Code sanguino software and Sanguino-0101r1.zip, and successfully compiled Sprinter.

However, I get invalid device signature.

[reprap.org]

Is the Atmega644P responding, should I use the avrdude -F optoion to override the signature check, or would this kill my microcontroller?

Thanks!

Followup - the ATMEGA644P needed a new boot loader. We think the sanguino may have been programmed using the hex load command, which would have overwritten the bootloader. Either than, or the old bootloader was custom and would only work with a previous version of the IDE. In any case the new bootloader seems to have fixed the problem.