Ethershield_webserver: DHCP won't work after reset or power cycle

[dekstop]

DHCP works fine in the Ethershield_webserver example directly after uploading the binary. However if the board is reset (via the reset push-button) or power cycled (unplug power source, plug back in) DHCP discovery will start but never yield an IP address.

It will work again after uploading a new binary; but again only once.

[yaleman]

I can't seem to get it working regardless of what I do on my Nanode. It sends the expected responses over the serial monitor as if the ethershield code was configured OK, but it never gets an address.

I'm running the board with a sparkfun FTDI breakout plugged into the board through USB as the sole power source, and the nanode is plugged into a Mikrotik RB750G router.