Linux/VAX boot protocol

Hello, Where can I find documentation on Linux/VAX boot protocol? The vmlinux images in vaxroot package: http://linux-vax.sourceforge.net/download/README.vaxroot-20010920 seem to have the following structure: +------------------+ 0x0000 | Padding | +------------------+ 0x0200 | Jump instruction | | Command line | +------------------+ 0x0300 | Kernel code | The jump instruction points to 0x104 so I assume the first 0x200 bytes are simply discarded? Pekka