calling a number for an ex friend who is, how do we say "on the run", got an answer from someone saying that he got the number from t-mobile and it was recycled and the person we were looking for isn't at that number.
im pretty sure that all companies do. i work at a call center and i run across that problem all the time (even with land lines) that someone else has the number now. i also know this cuz i called my old number (i have tmobile) is now some creepy old guy. lol.