Please: which processes – other than those relating to ZEVO – used the pool and/or the physical disk(s) at/around the time of the panic?
-None that I know of, its shared over afp, but it panicked overnight when none of the client machines were up. Its excluded from spotlight and TM. The machine was sitting under the stairs scrubbing, thats all.
How much memory in the MacPro3,1?
-4 Gb (currently out to grab 16)
Also, if you like, paste the content of the .panic file in its entirety. Its list of kernel extensions may provide clues, and so on.
I would love to but I never get the panic log, I did take a picture of the panic screen-

Kextstat
Index Refs Address Size Wired Name (Version) <Linked Against>
1 63 0 0 0 com.apple.kpi.bsd (10.8.0)
2 4 0 0 0 com.apple.kpi.dsep (10.8.0)
3 85 0 0 0 com.apple.kpi.iokit (10.8.0)
4 91 0 0 0 com.apple.kpi.libkern (10.8.0)
5 76 0 0 0 com.apple.kpi.mach (10.8.0)
6 27 0 0 0 com.apple.kpi.private (10.8.0)
7 46 0 0 0 com.apple.kpi.unsupported (10.8.0)
8 11 0xffffff7f80800000 0x4000 0x4000 com.apple.iokit.IOACPIFamily (1.3.0) <7 6 4 3>
9 20 0xffffff7f80804000 0x1f000 0x1f000 com.apple.iokit.IOPCIFamily (2.6.5) <7 6 5 4 3>
10 1 0xffffff7f80823000 0x45000 0x45000 com.apple.driver.AppleACPIPlatform (1.3.6) <9 8 7 6 5 4 3>
11 0 0xffffff7f80868000 0x2000 0x2000 es.osx86.driver.EvOreboot (1.0.3) <4 3>
12 0 0xffffff7f8086a000 0x2000 0x2000 org.tgwbd.driver.NullCPUPowerManagement (1.0.0d2) <7 4 3>
13 0 0xffffff7f8086c000 0x24000 0x24000 com.apple.driver.AppleIntelCPUPowerManagement (142.6.0) <7 6 5 4 3 1>
14 10 0xffffff7f80890000 0x1a000 0x1a000 com.apple.iokit.IOStorageFamily (1.6.3) <7 6 5 4 3 1>
15 0 0xffffff7f808aa000 0x12000 0x12000 com.apple.driver.DiskImages (289.1) <14 7 6 5 4 3 1>
16 0 0xffffff7f808bc000 0x8000 0x8000 com.apple.nke.applicationfirewall (2.1.14) <7 6 5 4 3 1>
17 2 0xffffff7f808c4000 0x3000 0x3000 com.apple.kext.AppleMatch (1.0.0d1) <4 1>
18 0 0xffffff7f808c7000 0x4000 0x4000 com.apple.security.quarantine (0) <17 7 6 5 4 2 1>
19 0 0xffffff7f808cb000 0x8000 0x8000 com.apple.security.sandbox (1) <17 7 6 5 4 2 1>
20 0 0xffffff7f808d3000 0x3000 0x3000 com.apple.security.TMSafetyNet (6) <7 6 5 4 2 1>
21 0 0xffffff7f808d6000 0x3000 0x3000 com.apple.driver.AppleAPIC (1.4) <4 3>
22 0 0xffffff7f808d9000 0x4000 0x4000 com.apple.driver.AppleSMBIOS (1.7) <7 4 3>
23 0 0xffffff7f808dd000 0x3000 0x3000 com.apple.driver.AppleHPET (1.5) <8 7 5 4 3>
24 0 0xffffff7f808e0000 0x6000 0x6000 com.apple.driver.AppleRTC (1.3.1) <8 5 4 3 1>
25 2 0xffffff7f808e6000 0x43000 0x43000 com.apple.iokit.IOHIDFamily (1.6.6) <7 6 5 4 3 1>
26 0 0xffffff7f80929000 0x4000 0x4000 com.apple.driver.AppleACPIButtons (1.3.6) <25 10 8 7 6 5 4 3 1>
27 0 0xffffff7f8092d000 0x5000 0x5000 org.netkas.FakeSMC (3.1.0) <8 7 5 4 3>
29 8 0xffffff7f80934000 0x3a000 0x3a000 com.apple.iokit.IOUSBFamily (4.2.4) <9 7 5 4 3 1>
30 0 0xffffff7f8096e000 0x17000 0x17000 com.apple.driver.AppleUSBEHCI (4.2.4) <29 9 7 5 4 3 1>
32 3 0xffffff7f80987000 0x7000 0x7000 com.apple.iokit.IOAHCIFamily (2.0.6) <5 4 3 1>
33 0 0xffffff7f8098e000 0x17000 0x17000 com.apple.driver.AppleAHCIPort (2.1.7) <32 9 5 4 3 1>
34 1 0xffffff7f809a5000 0x3000 0x3000 com.apple.driver.AppleEFIRuntime (1.4.0) <7 6 5 4 3>
35 0 0xffffff7f809a8000 0x1e000 0x1e000 com.LaCie.driver.PXHCD (1.0.8) <29 9 7 5 4 3>
36 0 0xffffff7f809c6000 0x5000 0x5000 com.apple.AppleFSCompression.AppleFSCompressionTypeZlib (1.0.0d1) <6 4 3 2 1>
37 1 0xffffff7f809cb000 0x2000 0x2000 com.apple.iokit.IOUSBUserClient (4.2.4) <29 7 5 4 3 1>
38 0 0xffffff7f809cd000 0x12000 0x12000 com.apple.driver.AppleUSBHub (4.2.4) <29 5 4 3 1>
39 0 0xffffff7f809df000 0x7000 0x7000 com.apple.driver.AppleEFINVRAM (1.4.0) <34 7 5 4 3>
40 0 0xffffff7f809e6000 0x4000 0x4000 com.apple.BootCache (31.1) <7 6 5 4 3 1>
41 0 0xffffff7f809ea000 0x15000 0x15000 com.apple.iokit.IOAHCIBlockStorage (1.6.4) <32 14 5 4 3 1>
42 0 0xffffff7f809ff000 0x3000 0x3000 com.apple.driver.XsanFilter (402.1) <14 5 4 3 1>
43 4 0xffffff7f80a02000 0x19000 0x19000 com.apple.iokit.IOSCSIArchitectureModelFamily (2.6.8) <5 4 3 1>
44 0 0xffffff7f80a1b000 0x9000 0x9000 com.apple.iokit.IOAHCISerialATAPI (1.2.6) <43 32 5 4 3 1>
45 4 0xffffff7f80a24000 0x9000 0x9000 com.apple.iokit.IOCDStorageFamily (1.6.1) <14 5 4 3 1>
46 2 0xffffff7f80a2d000 0x7000 0x7000 com.apple.iokit.IODVDStorageFamily (1.6) <45 14 5 4 3 1>
47 1 0xffffff7f80a34000 0x7000 0x7000 com.apple.iokit.IOBDStorageFamily (1.6) <46 45 14 5 4 3 1>
48 0 0xffffff7f80a3b000 0x13000 0x13000 com.apple.iokit.IOSCSIMultimediaCommandsDevice (2.6.8) <47 46 45 43 14 5 4 3 1>
49 0 0xffffff7f80a4e000 0x7000 0x7000 com.apple.iokit.SCSITaskUserClient (2.6.8) <43 14 5 4 3 1>
50 1 0xffffff7f80a55000 0x4000 0x4000 com.apple.driver.AppleUSBComposite (3.9.0) <29 4 3 1>
51 6 0xffffff7f80a59000 0x34000 0x34000 com.apple.iokit.AppleProfileFamily (41) <9 7 6 5 4 3 1>
53 1 0xffffff7f80a95000 0x1a000 0x1a000 com.apple.iokit.IONetworkingFamily (1.10) <7 6 5 4 3 1>
54 0 0xffffff7f80aaf000 0x34000 0x34000 com.lnx2mac.driver.RealtekRTL81xx (0.0.90) <53 9 5 4 3 1>
55 0 0xffffff7f80ae3000 0x3000 0x3000 com.apple.driver.AppleLPC (1.5.1) <9 5 4 3>
56 0 0xffffff7f80ae6000 0x2000 0x2000 com.apple.driver.AppleSMBusPCI (1.0.10d0) <9 5 4 3>
57 1 0xffffff7f80ae8000 0xe000 0xe000 com.apple.driver.IOPlatformPluginFamily (4.7.0a1) <8 7 6 5 4 3>
58 2 0xffffff7f80af6000 0xb000 0xb000 com.apple.driver.AppleSMC (3.1.0d5) <8 7 5 4 3>
59 0 0xffffff7f80b01000 0x11000 0x11000 com.apple.driver.ACPI_SMC_PlatformPlugin (4.7.0a1) <58 57 9 8 7 6 5 4 3>
60 1 0xffffff7f80b12000 0x141000 0x141000 com.getgreenbytes.filesystem.zfs (2012.09.14) <14 7 5 4 3 1>
61 0 0xffffff7f80c53000 0x6000 0x6000 com.getgreenbytes.driver.zfs (2012.09.14) <60 14 7 5 4 3 1>
62 2 0xffffff7f80c59000 0x8000 0x8000 com.apple.iokit.IOHDAFamily (1.7.9a4) <5 4 3 1>
63 8 0xffffff7f80c61000 0x28000 0x28000 com.apple.iokit.IOGraphicsFamily (2.2.1) <9 7 5 4 3>
64 1 0xffffff7f80c89000 0x14000 0x14000 com.apple.driver.AppleHDAController (1.7.9a4) <63 62 9 5 4 3 1>
65 0 0xffffff7f80c9d000 0x2a000 0x2a000 com.apple.driver.AppleIntelSNBGraphicsFB (6.3.6) <63 9 8 7 6 5 4 3 1>
66 3 0xffffff7f80cc7000 0xe000 0xe000 com.apple.iokit.IONDRVSupport (2.2.1) <63 9 7 5 4 3>
67 2 0xffffff7f80cd5000 0x2d2000 0x2d2000 com.apple.NVDAResman (6.3.7) <66 63 9 5 4 3 1>
68 0 0xffffff7f80fa7000 0x59e000 0x59e000 com.apple.nvidia.nvGF100hal (6.3.7) <67 9 4 3>
69 0 0xffffff7f81545000 0x4000 0x4000 com.dvdfab.kext.fabio (1) <45 43 5 4 3>
70 0 0xffffff7f81549000 0x5000 0x5000 com.apple.driver.AppleUSBMergeNub (4.2.4) <50 29 4 3 1>
71 0 0xffffff7f8154e000 0x6000 0x6000 com.apple.iokit.IOUSBHIDDriver (4.2.0) <29 25 5 4 3 1>
73 1 0xffffff7f8155c000 0x2000 0x2000 com.apple.iokit.IOSMBusFamily (1.1) <5 4 3>
74 0 0xffffff7f8155e000 0xb000 0xb000 com.apple.driver.AppleSMBusController (1.0.10d0) <73 9 8 5 4 3>
75 2 0xffffff7f81569000 0x5000 0x5000 com.apple.kext.OSvKernDSPLib (1.3) <5 4>
76 4 0xffffff7f8156e000 0x1c000 0x1c000 com.apple.iokit.IOAudioFamily (1.8.3fc2) <75 5 4 3 1>
77 0 0xffffff7f8158a000 0x4000 0x4000 com.apple.driver.AudioIPCDriver (1.1.6) <76 5 4 3 1>
78 1 0xffffff7f8158e000 0x7c000 0x7c000 com.apple.driver.DspFuncLib (1.7.9a4) <76 75 5 4 3 1>
79 0 0xffffff7f8160a000 0xb3000 0xb3000 com.apple.driver.AppleHDA (1.7.9a4) <78 76 66 64 63 62 5 4 3 1>
82 0 0xffffff7f81854000 0x5000 0x5000 com.apple.Dont_Steal_Mac_OS_X (7.0.0) <58 7 4 3 1>
85 1 0xffffff7f81c5f000 0xa000 0xa000 com.apple.iokit.IOSerialFamily (10.0.3) <7 6 5 4 3 1>
86 0 0xffffff7f81c69000 0xa000 0xa000 com.apple.iokit.IOBluetoothSerialManager (2.4.5f3) <85 7 5 4 3 1>
87 0 0xffffff7f81c73000 0xd7000 0xd7000 com.apple.GeForce (6.3.7) <67 66 63 9 7 6 5 4 3 1>
88 0 0xffffff7f81d4a000 0xc000 0xc000 com.apple.iokit.IOSurface (74.2) <7 5 4 3 1>
90 0 0xffffff7f81d58000 0x5000 0x5000 com.Cycling74.driver.Soundflower (1.5.2) <76 5 4 3>
91 0 0xffffff7f81d5d000 0x8000 0x8000 com.apple.driver.AppleMCCSControl (1.0.20) <63 9 7 5 4 3 1>
92 0 0xffffff7f81d65000 0x3000 0x3000 com.apple.driver.AppleProfileCallstackAction (20) <51 5 4 3 1>
94 0 0xffffff7f81d6d000 0x5000 0x5000 com.apple.driver.AppleUpstreamUserClient (3.5.7) <63 9 8 7 5 4 3 1>
95 0 0xffffff7f81d72000 0x2000 0x2000 com.apple.driver.AppleProfileKEventAction (10) <51 4 3 1>
97 0 0xffffff7f81d7d000 0x2000 0x2000 com.apple.driver.AppleProfileRegisterStateAction (10) <51 4 3 1>
98 0 0xffffff7f81d7f000 0x2000 0x2000 com.apple.driver.AppleProfileThreadInfoAction (14) <51 6 4 3 1>
99 0 0xffffff7f81d81000 0x2000 0x2000 com.apple.driver.AppleProfileTimestampAction (10) <51 5 4 3 1>
100 0 0xffffff7f81d83000 0x3000 0x3000 com.apple.driver.AppleProfileReadCounterAction (17) <51 6 4 3>
101 1 0xffffff7f81d86000 0xa000 0xa000 com.apple.nke.ppp (1.5) <7 6 5 4 3 1>
102 0 0xffffff7f81d90000 0xa000 0xa000 com.apple.filesystems.autofs (2.1.0) <7 6 5 4 3 1>
103 0 0xffffff7f81d9a000 0x7000 0x7000 com.apple.nke.l2tp (1.5) <101 7 6 5 4 3 1>
104 0 0xffffff7f81da1000 0x5000 0x5000 com.apple.driver.AppleHWSensor (1.9.3d0) <5 4 3>
105 0 0xffffff7f81da6000 0x3000 0x3000 com.bresink.driver.BRESINKx86Monitoring (8.0) <5 4 3>
106 3 0xffffff7f81da9000 0x2f000 0x2f000 org.virtualbox.kext.VBoxDrv (4.1.18) <7 5 4 3 1>
107 0 0xffffff7f81dd8000 0x8000 0x8000 org.virtualbox.kext.VBoxUSB (4.1.18) <106 37 29 7 5 4 3 1>
108 0 0xffffff7f81de0000 0x5000 0x5000 org.virtualbox.kext.VBoxNetFlt (4.1.18) <106 7 5 4 3 1>
109 0 0xffffff7f81de5000 0x6000 0x6000 org.virtualbox.kext.VBoxNetAdp (4.1.18) <106 5 4 1>
thanks again-