README.md in vagrant-rackspace-0.1.4 vs README.md in vagrant-rackspace-0.1.5

@@ -28,10 +28,20 @@
 ```
 
 Of course prior to doing this, you'll need to obtain an Rackspace-compatible
 box file for Vagrant.
 
+### CentOS / RHEL (sudo: sorry, you must have a tty to run sudo)
+
+The default configuration of the RHEL family of Linux distributions requires a tty in order to run sudo.  Vagrant does not connect with a tty by default, so you may experience the error:
+> sudo: sorry, you must have a tty to run sudo
+
+The best way to take deal with this error is to upgrade to Vagrant 1.4 or later, and enable:
+```
+config.ssh.pty = true
+```
+
 ## Quick Start
 
 After installing the plugin (instructions above), the quickest way to get
 started is to actually use a dummy Rackspace box and specify all the details
 manually within a `config.vm.provider` block. So first, add the dummy
@@ -96,9 +106,11 @@
 * `rackspace_auth_url` - The endpoint to authentication against. By default, vagrant will use the global
 rackspace authentication endpoint for all regions with the exception of :lon. IF :lon region is specified
 vagrant will authenticate against the UK authentication endpoint.
 * `public_key_path` - The path to a public key to initialize with the remote
   server. This should be the matching pair for the private key configured
+  with `config.ssh.private_key_path` on Vagrant.
+* `key_name` - If a public key has been [uploaded to the account already](http://docs.rackspace.com/servers/api/v2/cs-devguide/content/ServersKeyPairs-d1e2545.html), the uploaded key can be used to initialize the remote server by providing its name.  The uploaded public key should be the matching pair for the private key configured
   with `config.ssh.private_key_path` on Vagrant.
 * `server_name` - The name of the server within RackSpace Cloud. This
   defaults to the name of the Vagrant machine (via `config.vm.define`), but
   can be overridden with this.
 * `username` - The username with which to access Rackspace.