EC2 cookbook 'ec2' mash conflicts with ec2 key provided by ohai

DEBUG: Ohai Attribute: ec2 - {"ramdisk_id"=>"ari-b31cf9da", "public_hostname"=>"ec2-75-101-165-174.compute-1.amazonaws.com", "placement_availability_zone"=>"us-east-1a", "block_device_mapping_root"=>"/dev/sda1", "public_keys_0_openssh_key"=>"ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDCI3G0bbD3eYhtNiPiWSMSRnC4qaRCR62HWLrDbNBAIYVo/ssvf6EhA8wm7jeBsYoxsnEMudJddhO62XkDsU/zI7iLLh+lPF1GsgrBDjh6SNR665N3rXxiqrAbecP+Dvo/DdYEoXZ0YUyO8waKzHplYioR5fbMrbCqz4Twq9iWwkN4Y5BAJf7GBRBp/537l0MddESM8kzeI3/EsmoLauVdd+1ceaPWlM3VnFB1LH3mnxNQBnjpOcUFnX3YLaPnz/ZjXLubnomYxehkKxyicrhA9WYLGjq0PTkdHXXpei95GatrFNKBRMXvEbfDVS2BG7/4u/LvAfapHw+RpVdzIdjz searchlight-production\n", "product_codes"=>"82B9F900", "instance_id"=>"i-cb1623a2", "instance_type"=>"m1.large", "local_ipv4"=>"10.251.178.79", "block_device_mapping_ephemeral0"=>"sdb", "block_device_mapping_ephemeral1"=>"sdc", "reservation_id"=>"r-a3692eca", "public_ipv4"=>"75.101.165.174", "local_hostname"=>"ip-10-251-178-79.ec2.internal", "kernel_id"=>"aki-b51cf9dc", "block_device_mapping_ephemeral2"=>"sdd", "hostname"=>"ip-10-251-178-79.ec2.internal", "block_device_mapping_ephemeral3"=>"sde", "ami_id"=>"ami-fd9c7d94", "userdata"=>nil, "security_groups"=>"searchlight\n", "block_device_mapping_ami"=>"sda1", "ancestor_ami_ids"=>"ami-3f27c256\n", "ami_manifest_path"=>"grempe-ami-ubuntu-9-04-x86-64-base-underscore-20090706/image.manifest.xml", "ami_launch_index"=>"0"}

DEBUG: Loading attributes from confconfig/../cookbooks/ec2/attributes/ec2_recipe_options.rb:21:in `from_file': undefined method `has_key?' for true:TrueClass (NoMethodError)
from /usr/lib/ruby/gems/1.8/gems/chef-0.7.4/lib/chef/cookbook.rb:73:in `load_attributes'
from /usr/lib/ruby/gems/1.8/gems/chef-0.7.4/lib/chef/cookbook.rb:71:in `each'
from /usr/lib/ruby/gems/1.8/gems/chef-0.7.4/lib/chef/cookbook.rb:71:in `load_attributes'
from /usr/lib/ruby/gems/1.8/gems/chef-0.7.4/lib/chef/compile.rb:69:in `load_attributes'
from /usr/lib/ruby/gems/1.8/gems/chef-0.7.4/lib/chef/cookbook_loader.rb:117:in `each'
from /usr/lib/ruby/gems/1.8/gems/chef-0.7.4/lib/chef/cookbook_loader.rb:116:in `each_value'
from /usr/lib/ruby/gems/1.8/gems/chef-0.7.4/lib/chef/cookbook_loader.rb:116:in `each'
from /usr/lib/ruby/gems/1.8/gems/chef-0.7.4/lib/chef/compile.rb:68:in `load_attributes'
from /usr/lib/ruby/gems/1.8/gems/chef-0.7.4/lib/chef/client.rb:367:in `converge'

http://github.com/opscode/cookbooks/blob/d98496be02f510da377840c72990b42c37302f61/ec2/attributes/ec2_recipe_options.rb#L20

ec2 Mash.new unless attribute?("ec2")
ec2[:lvm] = Mash.new unless ec2.has_key?(:lvm)
ec2[:lvm][:use_ephemeral] = true unless ec2[:lvm].has_key?(:use_ephemeral)
ec2[:lvm][:ephemeral_mountpoint] = "/mnt" unless ec2[:lvm].has_key?(:ephemeral_mountpoint)
ec2[:lvm][:ephemeral_volume_group] = "ephemeral" unless ec2[:lvm].has_key?(:ephemeral_volume_group)
ec2[:lvm][:ephemeral_logical_volume] = "store" unless ec2[:lvm].has_key?(:ephemeral_logical_volume)
ec2[:lvm][:ephemeral_devices] = {
"m1.small" => [ "/dev/sda2" ],
"m1.large" => [ "/dev/sdb", "/dev/sdc" ],
"m1.xlarge" => [ "/dev/sdb", "/dev/sdc", "/dev/sdd", "/dev/sde" ],
} unless ec2[:lvm].has_key?(:ephemeral_devices)

suggest shifting 'ec2' key to 'ec2[:recipe_options] or something appropriately named.