Ultrabase 3, X230 tablet, and Ethernet/DisplayPort conflict

[abbiecd]

When plumbing in a second monitor, I observed I can use the DisplayPort and the Ethernet jack on either the dock or the laptop, but not both from the same unit (dock or laptop). When I have the dock DisplayPort connected, the dock Ethernet jack goes offline, but I can plug in to the laptop's accessible Ethernet jack. Or vice versa, when I have the DisplayPort connected to the laptop's accessible port, the laptop's Ethernet jack goes offline. This issue seems to defeat the purpose of having a dock.

I welcome ideas and suggestions. I saw mention of a different dock model having a firmware update, but it doesn't to the X230 tablet's dock.