I've written a command line app which may be useful, it can add the header to multiple sram files at once if required, please read the readme file before using. It's available here and the source is also included. http://www.infernal.currantbun.com/swcaddheader.zip , as Cyan said a while back, just using the emulator sram as is sometimes works, but it doesn't always work.
Chimano