chef fails to complete during vagrant-drupal 'vagrant up'.

vagrant-drupal error 1

$ vagrant up
There were warnings and/or errors while loading your Vagrantfile.
Your Vagrantfile was written for an earlier version of Vagrant,
and while Vagrant does the best it can to remain backwards
compatible, there are some cases where things have changed
significantly enough to warrant a message. These messages are
shown below.

Warnings:
* `config.vm.customize` calls are VirtualBox-specific. If you're
using any other provider, you'll have to find provider-specific configuration
to translate to manually in your Vagrantfile.

Bringing machine 'default' up with 'virtualbox' provider...
[default] Setting the name of the VM...
[default] Clearing any previously set forwarded ports...
[default] Fixed port collision for 22 => 2222. Now on port 2200.
[default] Creating shared folders metadata...
[default] Clearing any previously set network interfaces...
[default] Preparing network interfaces based on configuration...
[default] Forwarding ports...
[default] -- 22 => 2200 (adapter 1)
[default] -- 80 => 4567 (adapter 1)
[default] Running any VM customizations...
[default] Booting VM...
[default] Waiting for VM to boot. This can take a few minutes.
[default] VM booted and ready for use!
[default] The guest additions on this VM do not match the installed version of
VirtualBox! In most cases this is fine, but in rare cases it can
cause things such as shared folders to not work properly. If you see
shared folder errors, please update the guest additions within the
virtual machine and reload your VM.

Guest Additions Version: 4.1.6
VirtualBox Version: 4.2
[default] Setting hostname...
[default] Configuring and enabling network interfaces...
[default] Mounting shared folders...
[default] -- /srv
[default] -- /vagrant
[default] -- /tmp/vagrant-chef-1/chef-solo-1/cookbooks
[default] -- /tmp/vagrant-chef-1/chef-solo-2/cookbooks
[default] Running provisioner: VagrantPlugins::Chef::Provisioner::ChefSolo...
Generating chef JSON and uploading...
Running chef-solo...
stdin: is not a tty
[Fri, 05 Apr 2013 01:36:27 -0400] INFO: *** Chef 0.10.8 ***
[Fri, 05 Apr 2013 01:36:27 -0400] INFO: Setting the run_list to ["recipe[xforty]", "recipe[squid]", "recipe[drupal]", "recipe[initdb]"] from JSON
[Fri, 05 Apr 2013 01:36:27 -0400] INFO: Run List is [recipe[xforty], recipe[squid], recipe[drupal], recipe[initdb]]
[Fri, 05 Apr 2013 01:36:27 -0400] INFO: Run List expands to [xforty, squid, drupal, initdb]
[Fri, 05 Apr 2013 01:36:27 -0400] INFO: Starting Chef Run for drupal
[Fri, 05 Apr 2013 01:36:27 -0400] INFO: Running start handlers
[Fri, 05 Apr 2013 01:36:27 -0400] INFO: Start handlers complete.
[Fri, 05 Apr 2013 01:36:27 -0400] WARN: Missing gem 'right_aws'
[Fri, 05 Apr 2013 01:36:28 -0400] INFO: Missing gem 'mysql'
[Fri, 05 Apr 2013 01:36:28 -0400] ERROR: Running exception handlers
[Fri, 05 Apr 2013 01:36:28 -0400] ERROR: Exception handlers complete
[Fri, 05 Apr 2013 01:36:28 -0400] FATAL: Stacktrace dumped to /tmp/vagrant-chef-1/chef-stacktrace.out
[Fri, 05 Apr 2013 01:36:28 -0400] FATAL: NoMethodError: undefined method `[]' for nil:NilClass
Chef never successfully completed! Any errors should be visible in the
output above. Please fix your recipes so that they properly complete.