Funcunit sometimes generate invalid XML files

Using the ouput option to generate an xml file with test result sometimes create broken xml files. The command I use to generate the results xml is:

1.     ./js funcunit/open/phantomjs myapp/myapp_test.html -out myapp/docs/funcunit.xml

The problems is related to an invalid tag "testcase" inside the "testsuite"(s)  record during the process. All the tests are executed but somtimes the report process just add only a closing "</testcase>" tag, this breaks my build when it runs with our CI server (jenkings + xunit plugin). The test script contents is something like:

1.     steal('funcunit')
2.         // test modules
3.         .then('myapp/modules/expression/builder/builder_test.js')
4.         .then('myapp/modules/expression/factory/factory_test.js')
5.         .then('myapp/modules/expression/variable_selector/variable_selector_test.js')
6.         // etc ...

All tests pass, no errors inside them, no java exceptions, nothing wrong except for broken xml files.

My Environment:
- Ubuntu 12.04 64bit (tested even with 13.04 64bit)
- PhantomJS 1.9.1 (for 64bit platform)
- Jenkins 1.505
- XUnit 1.6.1