Apple today said a software problem — and not a faulty antenna design — is responsible for reports of poor reception by some iPhone 4 owners.

Apple admitted its signal strength miscalculation dates back to its original 2007 iPhone. It promised to fix the glitch in a few weeks, but did not directly address concerns that its antenna design causes reception problems for iPhone 4, its newest phone.

Apple's apology -- a relative rarity from the company known for its marketing savvy -- marked the third time in less than three weeks it had to apologize to customers of iPhone 4.

"Upon investigation, we were stunned to find that the formula we use to calculate how many bars of signal strength to display is totally wrong," Apple said in an open letter to customers published on Friday.

 Washington  state's ban on using a cellphone or texting while driving has led to nearly 670 citations between June 10 and July 1.

State Patrol Chief John Batiste believes compliance has increased since the violation became a primary offense, and that's making things easier for troopers.

"Those who continue to flout the law are now much easier to spot," Batiste said in a news release.

On June 10, the state's old law on cellphones and texting moved from being a secondary offense to a primary one, which means that troopers no longer need some other reason to stop a driver they see texting or using a cellphone.

The State Patrol did not give a formal grace period, as it typically does with new laws. Drivers who don't use a handsfree device can get a $124 ticket.

Along with the nearly 670 citations, nearly 500 warnings were issued.