Enjoying that old school MEdia Net data plan on your feature phone or smartphone? Get ready to kiss it goodbye should you ever choose to upgrade to a new phone. Proving once again that all good things must eventually end, AT&T has today made clear that any phone that it deems a “smartphone” will be subject to the same $30/month data plan that iPhone and BlackBerry users currently endure.In other words, any Palm, Windows Mobile or Symbian S60-based phone that is purchased from AT&T will have to be paired