i'm using Rockbox Utility v1.2.1:
http://download.rockbox.org/rbutil/win32/rbutilqt-v1.2.1.zipwith Gigabeat F40 and no matter how many times i choose "Install the bootloader" i always got "Bootloader is successful installed", here is screenshot:

however, when i look at GBSYSTEM\FWIMG folder indeed the original bootloader is renamed to FWIMG01.DAT.ORIG, but new FWIMG01.DAT is not created.
after i manually copy Rockbox bootloader FWIMG01.DAT file from here:
http://download.rockbox.org/bootloader/gigabeat/FWIMG01.DATto GBSYSTEM\FWIMG folder and after that from Rockbox Utility v1.2.1 run "Install the bootloader" again, then i got the following message:

so, it seems that Rockbox Utility v1.2.1 doesn't install the Rockbox bootloader FWIMG01.DAT, but only rename the original bootloader to FWIMG01.DAT.ORIG
is this some kind of bug in Rockbox Utility v1.2.1 or am i doing something wrong?
BTW, here:
http://www.rockbox.org/twiki/bin/view/Main/GigabeatFXPortis stated that latest version of the Rockbox bootloader FWIMG01.DAT file is from 21 April 2007, but the file here:
http://download.rockbox.org/bootloader/gigabeat/FWIMG01.DATis from 15 Oct 2008. is that newer version of the bootloader. does anyone know more details?