Apple CEO Steve Jobs addresses antenna problems in the iPhone 4 during a news conference today. (Kimberly White/Reuters)

Apple says it will give free protective cases to buyers of its latest iPhone model to alleviate the so-called “death grip” problem: holding the phone with a bare hand can muffle the wireless signal.

Apple Inc. CEO Steve Jobs announced the giveaway Friday at the company’s headquarters in California. Those who have already bought the phone and new buyers through Sept. 30 will all be eligible. People who already purchased the $29 “Bumper” cases will be refunded.

Earlier, Jobs declared, “We’re not perfect.”