P: Panel windows stacking order changes after hitting tab twice

Hi,

I am having an issue when I press tab to turn my palettes on and off with the tab key. They are re-ordering themselves alphabetically instead of how I left them. For example the layers palette will be visible above other palettes, I will press tab then do some painting/working, then when i press tab to turn the palettes back on I find that it is buried underneath other palettes. Is there any reason that the palettes should not be exactly as I left them vs. re-ordering themselves alphabetically?

Thanks