etch to lenny upgrade

[Randy Patterson <tech@patterson-pcc.com>]

I have changed my sources.list to read as below. I just changed the old one by 
changing etch references to lenny.

My current sources.list

deb ftp://debian.mirrors.tds.net/debian/ lenny main contrib non-free
deb-src ftp://debian.mirrors.tds.net/debian/ lenny main contrib non-free

When I do, "aptitude upgrade"

debian:/home/randy# aptitude upgrade
Reading package lists... Done
Building dependency tree... Done
Reading extended state information
Initializing package states... Done
Reading task descriptions... Done
Building tag database... Done
The following packages are unused and will be REMOVED:
  mkisofs
The following packages have been kept back:
  libdjvulibre15 libgphoto2-2 libgphoto2-port0 openoffice.org-calc 
openoffice.org-core
  openoffice.org-draw openoffice.org-kde openoffice.org-writer python-uno
The following packages will be upgraded:

<snip>

The following packages are RECOMMENDED but will NOT be installed:
  checkpolicy debconf-utils iproute-doc libjaxp1.3-java-gcj 
libxerces2-java-gcj mdetect
  mime-construct sane-utils setools vcdimager
204 packages upgraded, 0 newly installed, 1 to remove and 9 not upgraded.
Need to get 172kB of archives. After unpacking 32.8MB will be used.
Do you want to continue? [Y/n/?] y
Writing extended state information... Error!
E: I wasn't able to locate file for the linux-image-2.6.18-4-486 package. This 
might mean you need to manually fix this package.
E: Couldn't lock list directory..are you root?

I'm not sure how to continue from here?

Thanks!
Randy