Just hold down the ALT key while pressing the letters to spell out the word you need. Dial 1-800, pressing the ALT key on the CONTACTS. Let the BlackBerry cipher what numbers it needs, you won't need to!
Hope this isn't considered a threadjack, but tonight I was trying to refill a prescription through an automated system that required me to enter the scrip number followed by the # sign. No problem with the number, I tried entering the # sign both with and without the alt key, but got a Q in both cases.