I wrote:

The resource manager Rmgr (which is normally used to startup L4/x86 and Fiasco) handles the nitty-gritty details of telling the kernel where it should find its Sigma0 server.

In order to avoid any confusion: In a typical booting scenario on the x86, the Rmgr bootstrappig code runs even before the L4 or Fiasco kernel has been started. It is invoked directly by the boot loader and handles all initializations to be done before the kernel starts up: It finds the raw ELF binaries for the kernel and Sigma0 which the boot-loader has dropped in memory, interpretes them (i.e., moves them to their load addresses), configures the kernel (e.g., tells it the location of Sigma0 and Rmgr task entry points), and starts it.

For more information, please read the Rmgr manpage at URL:http://os.inf.tu-dresden.de/L4/l4libman/rmgr.html.

Michael