AR Test failure on latest mysql

getting this for 5.0.51a when running the AR test suite:

test_nil_defaults_for_not_null_columns(DefaultTest)
    [./test/cases/defaults_test.rb:17:in `test_nil_defaults_for_not_null_columns'
     ./test/cases/defaults_test.rb:14:in `each'
     ./test/cases/defaults_test.rb:14:in `test_nil_defaults_for_not_null_columns'
     ./test/cases/../../lib/../../activesupport/lib/active_support/testing/setup_and_teardown.rb:59:in `__send__'
     ./test/cases/../../lib/../../activesupport/lib/active_support/testing/setup_and_teardown.rb:59:in `run']:
name column should be DEFAULT "".
<""> expected but was
<nil>.