No way - just the opposite! In fact I think it worked the last time I ever saw it years later. That was an incredibly memorable piece of my childhood, and apparently that of many others' as well: http://dribbble.com/shots/680831-Fisher-Price-WIP-2 (wherein I also mention that feature).

I'm proud of the phone too. It taught kids their own home phone number in a really cool way. I didn't design the features, I just programmed them. I wonder how many kids called home because they learned their number from this toy.