In LV 6.1 an up you should be ablel to right click on the edge of the tab control when the tab-page in question is selected.
The bttom selcetion in the pop-up is "Reoder controls in page..."
selecting this option will switch editing modes to allow you to specify the ored, just like in a cluster.
I seem to remeber in older versions you had to drag the tabable controls off the tab control, specify the tabbing oder and then drag them back on. The oldest version I have on this machine is 6.1 so that all I can speak for at the moment.
I hope this helps,
Ben