I develop for Mer, on a smartq5 with Mer installed, so it might be possible for Maemo as well. I think the easiest way to start is to create a large enough ext2/3 filesystem on the device (can even be done in a loop device on the FAT32 partition), copy a completely installed SDK filesystem from there, and chrooting into it. There might be some work needed for getting the arm binaries of the compiler.