I chose the 2.6 image for the Netgear WGT634u.
Something wrong with one of the patchfiles. I'm not competent to chase it:
Applying ./patches/100-board_support.patch using plaintext:
patching file arch/mips/Kconfig
Hunk #2 succeeded at 244 (offset 18 lines).
patching file arch/mips/kernel/cpu-probe.c
Hunk #1 succeeded at 711 (offset -12 lines).
patching file arch/mips/kernel/proc.c
patching file arch/mips/Makefile
Hunk #1 FAILED at 571.
1 out of 1 hunk FAILED -- saving rejects to file arch/mips/Makefile.rej
patching file arch/mips/mm/tlbex.c
Hunk #1 succeeded at 892 (offset 12 lines).
patching file drivers/Kconfig
patching file drivers/Makefile
Hunk #1 FAILED at 77.
1 out of 1 hunk FAILED -- saving rejects to file drivers/Makefile.rej
patching file include/asm-mips/bootinfo.h
Hunk #1 succeeded at 213 (offset 1 line).
patching file include/asm-mips/cpu.h
patching file include/linux/pci_ids.h
Hunk #1 succeeded at 1981 (offset 31 lines).
Patch failed! Please fix ./patches/100-board_support.patch!
make[4]: *** [/usr/src/brianc/trunk/build_mipsel/linux-2.6-brcm47xx/linux-2.6.21.1/.prepared] Error 1
make[4]: Leaving directory `/usr/src/brianc/trunk/target/linux/brcm47xx-2.6'
. . . etc. . .