Got the same router, am almost certain that WAN is only 10 Base-T. I suspect this since the manual states that for the LAn lights, different colours represent diferent conneced speeds, whereas the WAN light doesnt support different colours, it only indicates connected or disconnected. Mine only allows 7.5Mb/sec through as well, incidently so it's a bit shy of 10 Base-T
What we need is a sticky on the forum which has compatability list for routers and the XL (20Mbs) package once some models have been identified as being suitable for XL or not.
I got led on my own investigation in this other thread:
http://www.cableforum.co.uk/board/87...or-router.html
Think I might go nuts and get that gigabit capable Linksys