Tried to run RubySpec with MRuby

gistfile1.txt

sasha:rubinius brian$ bin/mspec -t /source/mruby/bin/mruby
ruby 1.8.7 (2010-08-16 patchlevel 302) [i386-mingw32]
NODE_SCOPE:
  local variables:
  NODE_BEGIN:
    NODE_CALL:
      NODE_GVAR $:
      method='unshift' (141)
      args:
        NODE_CALL:
          NODE_CONST File
          method='expand_path' (279)
          args:
            NODE_STR "../../lib" len 9
            NODE_STR "(null)" len 6
    NODE_CALL:
      NODE_SELF
      method='require' (32)
      args:
        NODE_STR "mspec/commands/mspec-run" len 24
    NODE_CALL:
      NODE_SELF
      method='require' (32)
      args:
        NODE_STR "mspec" len 5
    NODE_CALL:
      NODE_CONST MSpecRun
      method='main' (281)
irep 104 nregs=6 nlocals=2 pools=4 syms=7
000 OP_GETGLOBAL	R2	'$:'
001 OP_GETCONST	R3	'unshift'
002 OP_STRING	R4	'../../lib'
003 OP_STRING	R5	'(null)'
004 OP_LOADNIL	R6
005 OP_SEND	R3	'(null)'	2
006 OP_LOADNIL	R4
007 OP_SEND	R2	'(null)'	1
008 OP_LOADSELF	R2
009 OP_STRING	R3	'mspec/commands/mspec-run'
010 OP_LOADNIL	R4
011 OP_SEND	R2	'File'	1
012 OP_LOADSELF	R2
013 OP_STRING	R3	'mspec'
014 OP_LOADNIL	R4
015 OP_SEND	R2	'File'	1
016 OP_GETCONST	R2	'(null)'
017 OP_LOADNIL	R3
018 OP_SEND	R2	'expand_path'	0
019 OP_STOP

#<NameError: uninitialized constant (null)>