Changing MAC addr programmatically

Hi. I was wondering if anyone knows how to change the MAC address on a Win2k/Win2003 box programatically?
I mean it’s in the registry, and even better, there is a utility that does that, called SMAC.
But, the changed MAC won’t be updated on the interface untill you either reboot or disable and reenable the network connection.
So is it possible to disable and reenable a network connection from a program? A VB 6, VB.net or C++ code would be great.
Thanks,
Victor