CPU panic, Double fault thread ??

[myuserid08]

I was working away writing an email when the keyboard became unresponsive, everything worked minus the keyboard. All of a sudden the macbook switched itself off and restarted.
Once it rebooted I was provided with the following report to submit to apple:

Mon Apr 20 14:15:28 2009
panic(cpu 0 caller 0x001A92D7): Double fault thread:0x64875d0, trapno:0x8, err:0x0, registers:
CR0: 0x80010033, CR2: 0x3ee3fff8, CR3: 0x0111b000, CR4: 0x00000660
RAX: 0x0000000000000001, RBX: 0x0000000000000e49, RCX: 0x0000000000000000, RDX: 0x0000000028578000
RSP: 0x000000003ee40000, RBP: 0x000000003ee43cf8, RSI: 0x00000000001a8ca7, RDI: 0x0000000003e63900
R8: 0xffffff8005b3f8e0, R9: 0x0000000000000000, R10: 0x0000000000000002, R11: 0x0000000000020000
R12: 0xffffff8005b39b34, R13: 0x000000002e71fdd4, R14: 0x0000000000000000, R15: 0x0000000000000000
RFL: 0x0000000000010002, RIP: 0xffffff00001bd140, CR2: 0x000000003ee3fff8

Backtrace (CPU 0), Frame : Return Address (4 potential args on stack)
0x4efde8 : 0x12b4f3 (0x45b13c 0x4efe1c 0x1335e4 0x0)
0x4efe38 : 0x1a92d7 (0x463ffc 0x64875d0 0x8 0x0)
0x4eff18 : 0x1a11c3 (0x4eff24 0xf 0x3e63900 0x0)
0x3ee43cf8 : 0x1aadf

Model: MacBook3,1, BootROM MB31.008E.B02, 2 processors, Intel Core 2 Duo, 2.2 GHz, 2 GB
Graphics: kHW_IntelGMA965Item, GMA X3100, spdisplays_builtin, 144 MB
Memory Module: BANK 0/DIMM0, 1 GB, DDR2 SDRAM, 667 MHz
Memory Module: BANK 1/DIMM1, 1 GB, DDR2 SDRAM, 667 MHz
AirPort: spairport_wireless_card_type_airport_extreme (0x14E4, 0x88), Broadcom BCM43xx 1.0 (5.10.38.27)
Bluetooth: Version 2.1.3f8, 2 service, 0 devices, 1 incoming serial ports
Network Service: Ethernet, Ethernet, en0
Serial ATA Device: Hitachi HTS542512K9SA00, 111.79 GB
Parallel ATA Device: HL-DT-ST DVDRW GSA-S10N
USB Device: Built-in iSight, (null) mA
USB Device: Apple Internal Keyboard / Trackpad, (null) mA
USB Device: IR Receiver, (null) mA
USB Device: Bluetooth USB Host Controller, (null) mA
USB Device: USB RECEIVER, (null) mA

Should I be worried or is this (hopefully) a one off. Could it be worth running the diagnostics cd?