Updating karmic

Question

Possible Duplicate:
Installing packages to end-of-lifed Ubuntu editions?

I have a server which fails to do any updates

$ sudo apt-get update
Ign http://security.ubuntu.com karmic-security Release.gpg
Ign http://gb.archive.ubuntu.com karmic Release.gpg
...
Ign http://gb.archive.ubuntu.com karmic-updates/multiverse Sources
Err http://gb.archive.ubuntu.com karmic/main Packages
  404  Not Found
...
W: Failed to fetch http://gb.archive.ubuntu.com/ubuntu/dists/karmic-updates/multiverse/source/Sources.gz  404  Not Found

E: Some index files failed to download, they have been ignored, or old ones used instead.

I have tried performing an upgrade, but that fails, presumable because it cant access anything above!

$ sudo apt-get dist-upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.

It currently is at :-

$ uname -a
Linux Gateway 2.6.31-23-generic-pae #75-Ubuntu SMP Fri Mar 18 19:14:10 UTC 2011 i686 GNU/Linux

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 9.10
Release:        9.10
Codename:       karmic

My question is, can I just replace the /etc/apt/sources.list with one from the current disto?

Currently contains lines like :-

deb http://security.ubuntu.com/ubuntu karmic-security main restricted
deb-src http://security.ubuntu.com/ubuntu karmic-security main restricted

Replace to so it has valid release :-

deb http://security.ubuntu.com/ubuntu oneiric-security main restricted
deb-src http://security.ubuntu.com/ubuntu oneiric-security main restricted

I see that it successfully Hits the packages.

...
Hit http://gb.archive.ubuntu.com oneiric-backports/restricted Packages
...

But just concerned if this is a good idea or not?