I made a custom Tobi-Duo (the only change to the Tobi-Duo schematic was the addition of the FTDI usb-serial) to do some in-line network functions, but I am having trouble getting the lan9221 chips to work.  I triple checked and had a friend independently verify that that I copied the  Tobi-Duo schematic perfectly, but U-boot says "No ethernet found".  I have several Overo Waters, all of which work on the Tobi-Duo, and on regular Tobi's.  

It looks to me like there is a hardware problem, but I have no idea how to diagnose it.  I cannot use ethtool to send messages to either interface because the kernel doesn't load any ethernet functionality because it can't communicate with the lan9221's when it boots up.  I could very easily diagnose the problem if I had a way to send messages out the MII.  I searched pretty deep in the archives and I couldn't find answers, so hopefully someone can answer these newbie questions, or point me to where they have been answered previously:

Is there some configuration that has to be done on the lan9221's to get them to work together on one Overo, or even by themselves?
How do I force an ethernet interface to be installed after Uboot decides there isn't ethernet?
The datasheet gives no information on the smsc lan9221 VDD18CORE pin other than a name, but on my board that pin produces 2.4V, while on the Tobi and Tobi duo it produces 1.8V.  Is this a configuration issue?