Kernel Oops - BUG: unable to handle kernel paging request at e08317d0; EIP is at add_netdev+0xa5/0xd0 [cisco_ipsec]

this appeared after I did install my truecrypt and my cisco vpnclient (available on demand, worked well under 10.4 and 10.10)
not very verbose bug as there is no external symptoms
happened this time after a reboot, with just a terminal window open

ProblemType: KernelOops
DistroRelease: Ubuntu 11.04
Package: linux-image-2.6.38-5-generic 2.6.38-5.32
Regression: Yes
Reproducible: Yes
ProcVersionSignature: Ubuntu 2.6.38-5.32-generic 2.6.38-rc6
Uname: Linux 2.6.38-5-generic i686
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.23.
Annotation: Your system might become unstable now and might need to be restarted.
Architecture: i386
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 0: AudioPCI [Ensoniq AudioPCI], device 0: ES1371/1 [ES1371 DAC2/ADC]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: dom 1546 F.... pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
 Card hw:0 'AudioPCI'/'Ensoniq AudioPCI ENS1371 at 0x2080, irq 16'
   Mixer name : 'Cirrus Logic CS4297A rev 3'
   Components : 'AC97a:43525913'
   Controls : 24
   Simple ctrls : 13
Date: Mon Mar 7 06:34:31 2011
Failure: oops
HibernationDevice: RESUME=UUID=3f7a1193-6cf1-4ef3-be78-f1bfda94ffa8
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Alpha i386 (20110302)
IwConfig:
 lo no wireless extensions.

 eth0 no wireless extensions.
Lsusb:
 Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 001 Device 002: ID 07ab:fc88 Freecom Technologies
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: VMware, Inc. VMware Virtual Platform
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.38-5-generic root=UUID=bce672a8-633d-462d-8e53-4a43db8cf7fc ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-2.6.38-5-generic N/A
 linux-backports-modules-2.6.38-5-generic N/A
 linux-firmware 1.48
RfKill:

SourcePackage: linux
Title: BUG: unable to handle kernel paging request at e08317d0
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 12/31/2009
dmi.bios.vendor: Phoenix Technologies LTD
dmi.bios.version: 6.00
dmi.board.name: 440BX Desktop Reference Platform
dmi.board.vendor: Intel Corporation
dmi.board.version: None
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 1
dmi.chassis.vendor: No Enclosure
dmi.chassis.version: N/A
dmi.modalias: dmi:bvnPhoenixTechnologiesLTD:bvr6.00:bd12/31/2009:svnVMware,Inc.:pnVMwareVirtualPlatform:pvrNone:rvnIntelCorporation:rn440BXDesktopReferencePlatform:rvrNone:cvnNoEnclosure:ct1:cvrN/A:
dmi.product.name: VMware Virtual Platform
dmi.product.version: None
dmi.sys.vendor: VMware, Inc.