Description of problem:
First time open a Form in designer, you can see error "no viable alternative at character '\'" appears in server.log.

Parts of the error log is pasted.

11:17:59,097 INFO [org.jboss.as] (Controller Boot Thread) JBAS015874: JBoss Red Hat JBoss BPMS 6.0.0.Beta-redhat-1 (AS 7.2.0.Final-redhat-8) started in 49813ms - Started 612 of 675 services (62 services are passive or on-demand)
11:18:33,495 INFO [org.guvnor.common.services.backend.config.ApplicationPreferencesLoader] (http-/127.0.0.1:8080-1) Setting preference 'type' to 'kjar'.
11:18:33,495 INFO [org.guvnor.common.services.backend.config.ApplicationPreferencesLoader] (http-/127.0.0.1:8080-1) Setting preference 'drools.dateformat' to 'dd-MMM-yyyy'.
11:18:33,495 INFO [org.guvnor.common.services.backend.config.ApplicationPreferencesLoader] (http-/127.0.0.1:8080-1) Setting preference 'drools.defaultlanguage' to 'en'.
11:18:33,495 INFO [org.guvnor.common.services.backend.config.ApplicationPreferencesLoader] (http-/127.0.0.1:8080-1) Setting preference 'rule-modeller-onlyShowDSLStatements' to 'false'.
11:18:33,495 INFO [org.guvnor.common.services.backend.config.ApplicationPreferencesLoader] (http-/127.0.0.1:8080-1) Setting preference 'designer.context' to 'designer'.
11:18:33,496 INFO [org.guvnor.common.services.backend.config.ApplicationPreferencesLoader] (http-/127.0.0.1:8080-1) Setting preference 'drools.defaultcountry' to 'US'.
11:18:33,496 INFO [org.guvnor.common.services.backend.config.ApplicationPreferencesLoader] (http-/127.0.0.1:8080-1) Setting preference 'designer.url' to 'http://localhost:8080'.
11:18:33,496 INFO [org.guvnor.common.services.backend.config.ApplicationPreferencesLoader] (http-/127.0.0.1:8080-1) Setting preference 'drools.datetimeformat' to 'dd-MMM-yyyy hh:mm:ss'.
11:18:33,496 INFO [org.guvnor.common.services.backend.config.ApplicationPreferencesLoader] (http-/127.0.0.1:8080-1) Setting preference 'build.enable-incremental' to 'true'.
11:18:33,496 INFO [org.guvnor.common.services.backend.config.ApplicationPreferencesLoader] (http-/127.0.0.1:8080-1) Setting preference 'designer.profile' to 'jbpm'.
11:19:02,825 INFO [org.jbpm.formModeler.service.bb.mvc.controller.ControllerServlet] (http-/127.0.0.1:8080-4) Application Directory: /tmp/July10/jboss-eap-6.1/standalone/deployments/business-central.war/.
11:19:02,825 INFO [org.jbpm.formModeler.service.bb.mvc.controller.ControllerServlet] (http-/127.0.0.1:8080-4) Application Config Directory: /tmp/July10/jboss-eap-6.1/standalone/deployments/business-central.war/./WEB-INF/etc
11:19:04,946 ERROR [stderr] (http-/127.0.0.1:8080-4) line 1:50 no viable alternative at character '\'
11:19:04,946 ERROR [stderr] (http-/127.0.0.1:8080-4) line 1:111 no viable alternative at character '\'
11:19:04,976 INFO [org.drools.compiler.kie.builder.impl.KieRepositoryImpl] (http-/127.0.0.1:8080-4) KieModule was added:MemoryKieModule[ ReleaseId=org.jbpm:HR:1.0]

Version-Release number of selected component (if applicable):

How reproducible:
Start BPMS DR6

Steps to Reproduce:
1. Add a user by ./add-user.sh and login
2. Click the "Process Authoring"
3. Click "Form Definition" in left bar and Click one form . You can see the error appears in server.log
Actual results:

Expected results:

Additional info: