method_missing blowing up

gistfile1.txt

2.0.0p247 :001 > def method_missing m,*args; [m.to_s,args].flatten.join " "; end
 => nil
2.0.0p247 :002 > "j".happy "hh"

2.0.0p247 :001 > def method_missing *args; args.join " "; end
 => nil
2.0.0p247 :002 > "j".happy
SystemStackError: stack level too deep
  from /Users/bjhaid/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/irb/workspace.rb:86
Maybe IRB bug!

2.0.0p247 :003 > def method_missing m,*args; args.join " "; end
Segmentation fault: 11

2.0.0p247 :001 > def method_missing m,*args; [m,args].flatten " "; end
 => nil
2.0.0p247 :002 > "j".happy hah
Segmentation fault: 11