Blackberry maker Research in Motion (RIM) has fired back at Apple over its claim that all smartphones suffer signal loss when held in a certain way.
"Apple's attempt to draw RIM into Apple's self-made debacle is unacceptable," Mike Lazaridis and Jim Balsillie, the co-chief executives of the Canada-based mobile phone maker, said in a statement.
It came after Apple chief executive Steve Jobs on Friday defended the new iPhone 4 from complaints about reception problems, saying other smartphones have similar antenna difficulties.
In a bid to demonstrate the iPhone is not the only smartphone that loses signal strength when gripped in a particular way, Jobs displayed a video of tests with devices from RIM, Taiwan's HTC and South Korea's Samsung.
Apple also created an online page on "smartphone antenna performance" at Apple.com/antenna which shows the tests with RIM's Blackberry Bold 9700, the HTC Droid Eris from HTC and the Samsung Omnia II.
But Lazaridis and Balsillie denounced Apple's claims as "misleading."
"Apple's claims about RIM products appear to be deliberate attempts to distort the public's understanding of an antenna design issue and to deflect attention from Apple's difficult situation," they said.
The RIM co-CEOs said their Ontario-based company "is a global leader in antenna design and has been successfully designing industry-leading wireless data products with efficient and effective radio performance for over 20 years.
"During that time, RIM has avoided designs like the one Apple used in the iPhone 4 and instead has used innovative designs which reduce the risk for dropped calls, especially in areas of lower coverage," they said.
Lazaridis and Balsillie also belittled Apple's offer to provide iPhone 4 customers with a rubber-and-plastic case, which fits around the phone and is intended to help alleviate the antenna issue.
"One thing is for certain, RIM's customers don't need to use a case for their BlackBerry smartphone to maintain proper connectivity," they said.
"Apple clearly made certain design decisions and it should take responsibility for these decisions rather than trying to draw RIM and others into a situation that relates specifically to Apple," they added.
Some iPhone 4 users have complained that they lose reception when covering the lower left corner of the phone -- whose unusual antenna wraps completely around the device -- in what has been referred to as the "death grip."
Apple's Jobs acknowledged the iPhone 4 drops slightly more calls than the previous version of the device, the iPhone 3GS, but said the issue had been overblown and was not unique to the iPhone 4.
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