There are still problems in the TCK5 interop/tx tests that run on CR3 with JTS transtactions installed.
The reason looks pretty the same as in JBPAPP-2583 issue.

Running on older JDK (jdk1.6.0_11) there are 2 failures in:
http://hudson.qa.jboss.com/hudson/job/tck5-jts-interop-tx/17/artifact/java-test-work/com/sun/ts/tests/interop/tx/session/stateful/bm/TxN_GlobalSingle/Client_test1_reverse.jtr
http://hudson.qa.jboss.com/hudson/job/tck5-jts-interop-tx/17/artifact/java-test-work/com/sun/ts/tests/interop/tx/webclient/jsp/URLClient_test13_reverse.jtr

However there should already be the fix in javaeetck, there are still 9 failures when run on jdk1.6.0_15:
http://hudson.qa.jboss.com/hudson/job/tck5-jts-interop-tx/18/testReport/unknownTestSuite.0/

Results are the same for both interop-tx and interop-tx-disabled.

http://hudson.qa.jboss.com/hudson/view/TCK5-EAP5-JTS/job/tck5-jts-interop-tx/
http://hudson.qa.jboss.com/hudson/view/TCK5-EAP5-JTS/job/tck5-jts-interop-tx-disabled/