YAML booleans.

Hi,

I'm not sure if this is an error or not:

irb(main):017:0> YAML.load("a: n")
YAML.load("a: n")
{"a"=>"n"}
irb(main):018:0> YAML.load("a: true")
YAML.load("a: true")
{"a"=>true}
irb(main):020:0> YAML.load("a: false")
YAML.load("a: false")
{"a"=>false}
irb(main):021:0> YAML.load("a: y")
YAML.load("a: y")
{"a"=>"y"}
irb(main):023:0> YAML.load("a: yes")
YAML.load("a: yes")
{"a"=>true}
irb(main):024:0> YAML.load("a: no")
YAML.load("a: no")
{"a"=>false}


What I'm expecting (after looking at example 4.27 in the History spec for 
YAML 1.0) is that both "a: y" and "a: n" should return the same as "a: yes" 
and "a: no" respectively.

Regards
  Ola Bini