On August 16 I upgraded Zone Alarm Internet Security Suite to version 9.3.014.000 with driver version 9.1.522.000. This put an end to a series of Windows 7 (64-bit) crashes that my wife and I had been experiencing ever since we started using our new PCs. Both of our PCs are HP TouchSmart machines running 64-bit Windows 7 with 6 GB of RAM. We had previously been using version 9.1.507.000.
On my PC, Windows was crashing on average once every two days with BugcheckCode 159 while the PC was in a sleep state. My wife's PC experienced similar crashes on average once every three days. As far as I could tell, the crashes occurred at random times as if they were a statistical Poisson process. On these assumptions, if I had not fixed the problem that was causing these crashes, the likelihood of getting a run of 14 consecutive days without a crash would have been less than 0.1%. Although I did previously have a run of 10 days without a crash (over a period of 200 days), it appears very unlikely that my recent crash-free experience on two separate machines is due to chance alone. I am quite confident that the problem has been fixed.
From what I have learned from internet chat sites concerned with these crashes, it appears that Windows 7 crashes with BugcheckCode 159 are likely to be caused by some driver that does not adhere properly to the Windows ACPI power management protocol. It appears likely that version 9.3.014.000 of Zone Alarm fixed a problem with a Zone Alarm driver that was causing these crashes.