LVM device-mapper errors

[Paul Reilly <paul@astropaul.com>]

I'm getting various lvm/devmapper errors when creating and removing
snapshots on debian Sarge.

  device-mapper ioctl cmd 9 failed: Cannot allocate memory
  Couldn't load device 'myvg-www2_snapshot'.
  Unable to deactivate logical volume "myvg-www2_snapshot"

I am using:

 lvm2                            2.01.04-5
 libdevmapper1.01                1.01.00-4
 kernel 2.6.10

Has anyone else experienced these types of errors?
Is there an updated package available?

I am a bit reluctant to update from sources, as I have a lot
of data in my LVM volumes.

Paul