Can you post a link to this Ralink SDK / source?
we can't provide this info.Sorry
Actually, you are not only allowed to give out the sourcecode to U-boot, you're actually legally required to give it out. The version of U-boot you use is a modified 1.1.3. According to the COPYING file in the original (downloadable at ftp://ftp.denx.de/pub/u-boot/u-boot-1.1.3.tar.bz2
) it's licensed under the GPL2 and you should give out (an offer to provide the) source code if you send out binaries in any form, including in the flash of the Carambola itself.