Cannot find swap device after upgrade from Dapper to Edgy

[Rudolf Petzolt]

error-messages:
Jan 28 01:05:20 localhost kernel: [17181834.964000] swsusp: Cannot find
swap device, try swapon
Jan 28 10:08:47 localhost kernel: [17179614.560000] Unable to find
swap-space signature
Jan 28 10:08:47 localhost kernel: [17179617.060000] Unable to find
swap-space signature

Tried this:
root at snjo:/home/rudi# swapon -a
swapon: /dev/disk/by-uuid/4d9dd986-5d9b-4b4c-8a5e-e5db1cf8ba34: Invalid
argument

This is my fstab:
# /etc/fstab: static file system information.
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
proc            /proc           proc    defaults        0       0
# /dev/hda1 -- converted during upgrade to edgy
UUID=2c272b77-84ba-4e04-9cf3-6cab89856728 / ext3
defaults,errors=remount-ro 0 1
# /dev/hdb5 -- converted during upgrade to edgy
UUID=4d9dd986-5d9b-4b4c-8a5e-e5db1cf8ba34 none swap sw 0 0
/dev/hdd        /media/cdrom0   udf,iso9660 user,noauto     0       0
/dev/hdc        /media/cdrom1   udf,iso9660 user,noauto     0       0
/dev/fd0        /media/floppy0  auto    rw,user,noauto  0       0
/dev/hdb1       /mediator	ext3    user,noauto	1       2

-- 
Rudolf Petzolt <petzolt at online.no>