Thanks to some text message-savvy grandchildren, North Carolina drivers whose license plates have the potentially offensive "WTF" letter combination can replace the tags for free.

The News & Observer of Raleigh reported Tuesday the state Division of Motor Vehicles has notified nearly 10,000 holders of license plates with the letter combination. Officials learned last year the common acronym stands for a vulgar phrase in e-mail and cell phone text messages.

The DMV recently realized the same letters appeared on the sample license plate on its own Web site. Officials are trying to remove the plate from the site.

"I can't believe it," DMV Commissioner Bill Gore told the newspaper on Monday when alerted to the situation. "Obviously, I didn't know it was there."

DMV officials got word of the plates last July when a 60-year-old technology teacher from Fayetteville complained about the plate after her teenage grandchildren clued her in.