What are you doing when this happens (programs etc.) ? I see you said multiple macbooks so there is a start.
Most of the time it's things like when you close the lid with an external monitor and it doesn't wake anymore... If you press shutdown button 5 secs, and reboot then... Probably some driver problem or so.
Console goes like this:
I noticed this macbook went into hybernation... didn't notice if it was always this case.
Wed Mar 21 22:26:29 2007
panic(cpu 1 caller 0x001A429B): Unresolved kernel trap (CPU 1, Type 14=page fault), registers:
CR0: 0x8001003b, CR2: 0x13f73cfc, CR3: 0x00d5c000, CR4: 0x000006e0
EAX: 0x03ce8c00, EBX: 0x03ce8c00, ECX: 0x0000000c, EDX: 0x241f7038
CR2: 0x13f73cfc, EBP: 0x13f93f78, ESI: 0x13f73cfc, EDI: 0x005666ce
EFL: 0x00010206, EIP: 0x005666f3, CS: 0x00000008, DS: 0x13f90010
Backtrace, Format - Frame : Return Address (4 potential args on stack)
0x13f93db8 : 0x128d08 (0x3cb134 0x13f93ddc 0x131de5 0x0)
0x13f93df8 : 0x1a429b (0x3d0e4c 0x1 0xe 0x3d0670)
0x13f93f08 : 0x19ada4 (0x13f93f18 0x2 0xe 0x3220048)
0x13f93f78 : 0x13d7d9 (0x3ce8c00 0x13f73cfc 0x19e23a 0x25c3f5c)
0x13f93fc8 : 0x19ac1c (0x0 0x0 0x19e0b5 0x3b8ca10) Backtrace terminated-invalid frame pointer 0x0
Kernel version:
Darwin Kernel Version 8.9.1: Thu Feb 22 20:55:00 PST 2007; root:xnu-792.18.15~1/RELEASE_I386
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