arduino/sanguino with ATmega644 (non P)

Hi,
since I've got an ATmega644 (non P) lying around, I am wondering if it cannot be used in an sanguino.

I flashed it with the bootloader that comes with the sanguino software, set the fuses but when I now try to upload a sketch with the arduino software I get an error:
avrdude: Expected signature for ATMEGA644P is 1E 96 0A
Double check chip, or use -F to override this check.

Can someone please point me to where I could either add the "-F" option or change the chip to ATMEGA644?

thanks

In the boards.txt file, change
sanguino.build.mcu=atmega644p
to
sanguino.build.mcu=atmega644

everything else can remain the same

actually I replaced every occurance of atmega644p with atmega644 before, but i DIDN'T RESTART the arduino software, so it didn't work and I changed it back.

But after a restart, everything is working fine, thanks @mem

What are the dimensions of a atmega644P'U DIP40 in milimeters ?

You mean, as in 40 pin part, 0.6" wide, 0.1" lead spacing?