Release 2.0 is available upstream (latest release). Release 1.6.1 is available upstream (this fixes important issues that exist release 1.5). Please update to either release 1.6.1 or 2.0, to support mixed-stepping hardware configurations (when processors of different steppings are used. These are far more common in "upgraded" servers than one would expect), and to fix some annoying bugs in release 1.5. Thank you!
Thank you, 2.0 is in the tree now.