by , 7:50 AM EDT, June 13th, 2007

Apple's revolving door on ZFS has spun back around again. Now the word out of Cupertino is that the ZFS file system will be included in Mac OS X 10.5, but in a limited capacity, according to InformationWeek.

Several days before the Steve Jobs keynote at Apple's World Wide Developers Conference, Sun CEO Jonathan Schwartz claimed that Mac OS X 10.5, or Leopard, would include his company's 128-bit ZFS file system. On keynote day, however, Mr. Jobs said nothing about ZFS.

Afterwards, Brian Croll, Apple's senior director of product marketing for Mac OS, commented "ZFS is not happening."

Later, an Apple spokesperson attempted to clarify Mr. Croll's comments to InformationWeek by stating that ZFS actually will be included in Leopard, but only as a read-only option from the command line.

And finally, Mr. Croll added his own clarification to the spokesperson's clarification. "ZFS is not the default file system for Leopard," he said. "We are exploring it as a file system option for high-end storage systems with really large storage. As a result, we have included ZFS - a read-only copy of ZFS - in Leopard."

It appears that, at least for now, Apple's HFS+ file system is here to stay. Macs will continue to use the familiar file system that has been a part of Apple's operating system for about ten years, but ZFS may be an option for some high-capacity storage systems.

In the end, it looks like both Mr. Schwartz's and Mr. Croll's original comments were right... at least a little bit. ZFS will be included in Mac OS X, but it "is not happening" in the sense that it won't be Leopard's default file system.