Configuring the boot splash screens
Is a raw framebuffer bitmap that is gzipped.
Here is a basic description: http://svn.openmoko.org/trunk/src/host/splash/README
Use dfu-util to send to the OpenMoko.
NOTE... the README states you must issue two U-Boot commands to enable the flashed splash image to appear on the screen at boot:
setenv splashimage nand read.e 0x32000000 splash 0x5000\; unzip 0x32000000 0x33d00000 0x96000 saveenv
This is already a part of the U-Boot image received in the phone... however, if you make changes to your splash image, you may need to change the splashimage variable to compensate!
0x5000 is the (maximum) size of the compressed file -- the splash.gz that gets created. If you've made changes to your image you may have increased the compressed size; if it exceeds 0x5000 (20480) bytes, the entire image will not load unless you increase this value in your splashimage U-Boot environment variable.