How to choose which network connection provides the default gateway in Windows XP

Question

Possible Duplicate:
How can I change the binding order of network adapters in Windows 7?

I have a laptop with an integrated NIC and a WiFi connection. Both the wired and wireless networks I am using can access the Internet. Win XP is routing all traffic through the wireless network. I want to force it to route everything through the wired network when it is available (i.e. when I am sitting at my desk with the laptop docked) and through the wireless when that is the only option (i.e. when I have undocked my laptop and carried it to a conference room, or if I am out of the office working on a different WiFi network).

The wireless connection cannot be established until after I am logged into Windows, so it's always the second network to become available to the OS.

I have manually overridden the metric values in the TCP/IP configurations so that the NIC has metric 10 and the WiFi has metric 20. However, Windows is still picking the WiFi adapter's address as the Default Gateway, so this isn't helping. If I manually disable and re-enable the WiFi adapter, then it will switch the default gateway to the wired network and stay that way until I shutdown Windows.

How can I tell Windows XP not to replace the default gateway when the WiFi connection is first enabled?