When Max & I were in FL, I wanted to call WDW DINE from the Park to see about moving a ressie. I pulled out my phone & realized that that wasn't going to work....I have a Propel with a full QWERTY keypad Max has a Blackberry.
We ducked into a shop & they called for us.
But, just a tip - if you have a qwerty on your cell - save WDW DINE in your phonebook!