"publish xUnit test report" post-build step constantly fails with such output:

10:31:18 [xUnit] [INFO] - Starting to record.
10:31:18 [xUnit] [INFO] - Processing JUnit
10:31:19 [xUnit] [INFO] - [JUnit] - 3 test report file(s) were found with the pattern 'results-pjsip/*.xml' relative to '/tmp/workspace/_SIP/pjsip_c' for the testing framework 'JUnit'.
10:31:20 [xUnit] [ERROR] - The result file '/tmp/workspace/_SIP/pjsip_c/results-pjsip/presence-tests-func-1372749982.89.xml' for the metric 'JUnit' is not valid. The result file has been skipped.
10:31:20 [xUnit] [INFO] - Fail BUILD because 'set build failed if errors' option is activated.
10:31:20 [xUnit] [INFO] - There are errors when processing test results.
10:31:20 [xUnit] [INFO] - Skipping tests recording.
10:31:20 [xUnit] [INFO] - Stop build.

I have turned on the debug according to https://issues.jenkins-ci.org/browse/JENKINS-12900?focusedCommentId=159687&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-159687

but unfortunately xUnit log contains only such records, which related to the other xUnit job, and not to failed one:

Jul 2, 2013 8:44:39 AM com.thalesgroup.hudson.plugins.xunit.service.XUnitService infoSystemLogger
INFO: [xUnit] - Converting '/var/lib/jenkins/jobs/SIP/jobs/b2bua_functest_report_cron/workspace/branch/mr30/results/TEST-test.ft8151_attended_transfer_basics-ft8151_attended_transf
er_basics-ua2_wrong_user-1372743790288.xml' .

Affected .xml report is in attachment.

Please, prompt how I can get more verbose "parsing" log for this issue.