San Francisco, Jul 17 (DPA): Hoping to stem growing disgruntlement over its latest iPhone 4, Apple Friday announced it would provide free protective covers and offer a full refund to owners whose phones suffered from widespread antenna glitches.

Apple Chief Executive Officer Steve Jobs made the offer at a hastily convened press conference after the company faced growing fallout over the propensity of the hit new phone to drop calls when held in a certain way.

Jobs said Apple will give free bumper cases to everyone who bought or will buy the phone through Sep 30. Apple will refund the cost to anyone who has already bought a bumper case, and will offer a full refund within 30 days of the phone's purchase price to users who remain unsatisfied.

Jobs said the functioning of the phone's external antenna was impacted when the phone is held over its lower left-hand corner, blocking the signal.

Apple "screwed up" with the signal algorithm of the phone, Jobs said. But he insisted that the antenna problems were common to all smartphones, and said the issue was blown "so out of proportion, it's incredible".

Apple has sold some three million iPhone 4's since they went on sale June 24, making the device the company's fastest-selling product in history.

Prior to Friday's admission by Jobs, Apple had repeatedly downplayed the problem, attributing it to a software fault that allegedly overestimates the signal strength that the phone is receiving.

But the respected consumer organization Consumer Reports tested the device, confirming that the problem is with the antenna and called on Apple to fix the issue.

Financial news agency Bloomberg reported that the company's chief antenna engineer had warned about the glitch months before the launch, but that Jobs decided to ignore the concerns.

The report said that the glitch is caused because the case is split into distinct sections that are used as separate antennas for different wavelengths and that holding the phone a certain way causes a short circuit between the antennas. Cladding the phone in a bumper case insulates the metal thereby preventing the short circuit.

The Wall Street Journal said that Apple's bid to preserve the phone's secrecy ahead of the launch meant that the phones were only tested in "stealth mode" in bodies that disguise the phone's real look. The tests were also carried out in a way that prevented the phones being held, the report said.