Device Tree enabled u-boot for kirkwood?

I've been playing with 3.5 and now 3.6 kernels using Device Tree on my GoFlex. I've been trying to come up with a config that will allow DT kernels to boot using the updated u-boot without config/env changes if possible. So far, I can fire up kernels if I append the .dtb to the kernel and boot with no bootenv. In theory the kernel supports options to append legacy kernel options to the ones in the DT, or replace the DT ones entirely with the legacy ones but so far I've not been able to make either work.

Later u-boots are supposed to support DT directly, allowing one to load a dtb file after loading the kernel just like you load an initrd. They're also supposed to allow loading of zImages directly. Is the u-boot version that was built to handle 3.2 and newer kernels capable of being configured for DT support? My initial tests didn't show native zImage or dtb file loading support.

You've seen my post here? Look in the U-Boot patch file.
http://forum.doozan.com/read.php?2,8177,9332#msg-9332

U-Boot needs to be built with 'CONFIG_OF_LIBFDT'. You'll see new options like 'fdt' when doing 'help'. I'm not sure if arcNumber still works once it's built like this. I don't know about zImage either.

I know that the U-Boot env 'bootargs' will override the one in the DT blob.