We followed the code from boot.php, were somewhat surprised to find quite some things hardcoded. In bootmenu.class.php on line 536 we found:
else if ($Task->get('typeID') == 4)
print "$this->memdisk iso raw\n";
We copied this and added exactly the same with ur own task ID (24) and added our boot lines. It now works in combination with the taskTypes entry. (in which ttKernel or ttKernelArgs do nothing apparently)
Depending on your setup (you haven’t told us anything about that yet - OS, version, virtual/physical, partition layout, free space or second hard drive?) you probably need to adjust most of the tings mentioned there. But this should give you a good starting point. For further assistence we do need more information!