$ bin/jruby -J-esa test/mri/psych//test_yaml.rb 
MiniTest::Unit::TestCase is now Minitest::Test. From /Users/cmeier/projects/active/jruby/test/mri/psych/helper.rb:8:in `<module:Psych>'
MiniTest::Unit::TestCase is now Minitest::Test. From test/mri/psych//test_yaml.rb:13:in `<top>'
Run options: --seed 52993

# Running:

..........E......................................................

Finished in 1.444946s, 44.9844 runs/s, 187.5503 assertions/s.

  1) Error:
Psych_Unit_Tests#test_symbol_cycle:
Java::JavaLang::AssertionError: 
    org.jruby.util.ByteList.setEncoding(ByteList.java:1399)
    org.jruby.RubySymbol.associateEncoding(RubySymbol.java:161)
    org.jruby.RubySymbol.newSymbol(RubySymbol.java:206)
    org.jruby.ir.operands.Symbol.createCacheObject(Symbol.java:35)
    org.jruby.ir.operands.ImmutableLiteral.cachedObject(ImmutableLiteral.java:63)