I’ve added support for the BT Voyager 2110 to OpenWrt. A patch has been submitted to the openwrt-devel mailinglist, and has been accepted to trunk. If you aren’t comfortable with compiling OpenWrt from source, I’ve uploaded precompiled binaries based on trunk r26936. Just be aware that OpenWrt does not support the ADSL functionality of this router yet (waiting on Broadcom to release the ADSL driver source code).
I take no responsibility for any bricked devices, although if you manage to do it please tell me! It’s actually quite difficult to properly brick a brcm63xx device with a CFE bootloader.