Gem.const_missing causes infinite loop

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$ ruby-1.9 -v
ruby 1.9.0 (2008-04-28 revision 15721) [i686-linux]

$ ruby-1.9 -ve ‘p Gem::A’
/usr/local/lib/ruby/1.9.0/rubygems.rb:79: warning: already initialized
constant MUTEX
/usr/local/lib/ruby/1.9.0/rubygems.rb:81: warning: already initialized
constant RubyGemsPackageVersion
/usr/local/lib/ruby/1.9.0/rubygems.rb:86: warning: already initialized
constant WIN_PATTERNS
/usr/local/lib/ruby/1.9.0/rubygems.rb:79: warning: already initialized
constant MUTEX
/usr/local/lib/ruby/1.9.0/rubygems.rb:81: warning: already initialized
constant RubyGemsPackageVersion
/usr/local/lib/ruby/1.9.0/rubygems.rb:86: warning: already initialized
constant WIN_PATTERNS
/usr/local/lib/ruby/1.9.0/rubygems.rb:79: warning: already initialized
constant MUTEX
/usr/local/lib/ruby/1.9.0/rubygems.rb:81: warning: already initialized
constant RubyGemsPackageVersion
/usr/local/lib/ruby/1.9.0/rubygems.rb:86: warning: already initialized
constant WIN_PATTERNS
/usr/local/lib/ruby/1.9.0/rubygems.rb:79: warning: already initialized
constant MUTEX
/usr/local/lib/ruby/1.9.0/rubygems.rb:81: warning: already initialized
constant RubyGemsPackageVersion