If you are using ‘svn switch‘ on your deployer and you have older servers (Ubuntu 10.04 for example) the standard repo version of SVN will be 1.6, and won’t support the command.
What you need to do is upgrade the SVN client to version 1.7x with a PPA package. I suggest using the following commands:
sudo aptitude install python-software-properties; sudo apt-add-repository ppa:svn/ppa; sudo aptitude update; sudo aptitude safe-upgrade
From top to bottom, it installs the software you need to add a PPA, adds the PPA, updates the repo index and then upgrades all packages (which will upgrade SVN too).
A PPA is a Personal Package Archives for reference.
Using a Personal Package Archive (PPA), you can distribute software and updates directly to Ubuntu users. Create your source package, upload it and Launchpad will build binaries and then host them in your own apt repository.
That means Ubuntu users can install your packages in just the same way they install standard Ubuntu packages and they’ll automatically receive updates as and when you make them.
The PPA above is from the SVN development team, so I assume it to be trustworthy.
After completing you should get this:
svn --version svn, version 1.7.7 (r1393599) compiled Oct 26 2012, 08:48:56