Rumors of a new quad-core "A6" processor for Apple's next iPad and iPhone have been circulating for months, and on Friday new information came to light that will fuel the speculation.

According to a report by Mark Gurman on the 9to5mac web site, the code for Apple's iOS 5.1 beta operating system, which developers can access for testing before the software is released to the public, hints at compatibility with quad-core CPUs.

The iOS 5.1 beta describes three different processor variations, making reference to "/cores/core.3," as well as "/cores/core.0," which identifies a single-core CPU, and "/cores/core.1," which identifies a dual-core processor.

Based on Apple's naming convention so far, Gurman says, ".cores/core.3" would refer to a quad-core chip. The rumor is that such a quad-core processor would be called the A6 and be used in the expected iPad 3.

"Apple leaving references to quad-core chips in the iOS 5.1 beta is notable because iOS 5.1 is the software currently being tested against the third-generation iPad," Gurman wrote. "We cannot conclude that due to iOS 5.1 including quad-core processor references, Apple's next-generation iPad and iPhone will include a quad-core chip, but it seems reasonable based on Apple starting with a single-core chip in 2010 and moving to dual-core in 2011. A quad-core chip in 2012 would fit the pattern."

The latest speculation indicate the release of iPad 3 in March 2012 and iPad 4 in October, although it sounds had for Apple to release two proucts within 6 months.