Ubuntu : update openssh from 4.7 to a newer version ?

I have a server running on Ubuntu 8.04 LTS.

This version provides openssh 4.7.

I need to have a chroot environment for sftp.

I read chroot was possible with at least openssh 4.9.

So, how do I update easily to a newer version of openssh?

I specify its a remote server. So i can take the risk to damage the ssh server.

From serverfault Arkan

• The quick answer to this is: Upgrade to a newer version of Ubuntu. According to the online Ubuntu packages database, the version of openssh-server you need is in the Jaunty and later releases.

  Arkan : Is it possible to just upgrade openssh without upgrading the distrib?

  Steven Monai : Yes, it is possible to do this by adding an entry to `/etc/apt/sources.list` for an Ubuntu repository that contains the desired version of `openssh-server`.

  Arkan : Thanks for your answers. I'm gonna try this. Keep you in touch

  Arkan : Excuse me, what is the repository to add to sources.list to enable a 5.x openssh version ? I'm a little bit confused :?
  From Steven Monai

• I believe this page http://www.minstrel.org.uk/papers/ describes a process for old versions of OpenSSH. This other site http://www.linuxjournal.com/content/creating-chroot-sftp-jails-jailkit describes another approach.

  Google is your friend!

  From RedGrittyBrick

• I use MySecureShell on my Ubuntu Hardy servers to provide that same functionality.

  From KayakJim