[ERROR] Failed to execute goal org.apache.maven.plugins:maven-enforcer-plugin:1.3.1:enforce (enforce-java-version) on project mod_cluster-parent: Execution enforce-java-version of goal org.apache.maven.plugins:maven-enforcer-plugin:1.3.1:enforce failed: An API incompatibility was encountered while executing org.apache.maven.plugins:maven-enforcer-plugin:1.3.1:enforce: java.lang.ExceptionInInitializerError: null
[ERROR] -----------------------------------------------------
[ERROR] realm =    plugin>org.apache.maven.plugins:maven-enforcer-plugin:1.3.1
[ERROR] strategy = org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy
[ERROR] urls[0] = file:/Users/rhusar/.m2/repository/org/apache/maven/plugins/maven-enforcer-plugin/1.3.1/maven-enforcer-plugin-1.3.1.jar
[ERROR] urls[1] = file:/Users/rhusar/.m2/repository/org/apache/maven/reporting/maven-reporting-api/2.0.9/maven-reporting-api-2.0.9.jar
[ERROR] urls[2] = file:/Users/rhusar/.m2/repository/org/apache/maven/doxia/doxia-sink-api/1.0-alpha-10/doxia-sink-api-1.0-alpha-10.jar
[ERROR] urls[3] = file:/Users/rhusar/.m2/repository/commons-cli/commons-cli/1.0/commons-cli-1.0.jar
[ERROR] urls[4] = file:/Users/rhusar/.m2/repository/org/codehaus/plexus/plexus-interactivity-api/1.0-alpha-4/plexus-interactivity-api-1.0-alpha-4.jar
[ERROR] urls[5] = file:/Users/rhusar/.m2/repository/org/codehaus/plexus/plexus-utils/1.5.8/plexus-utils-1.5.8.jar
[ERROR] urls[6] = file:/Users/rhusar/.m2/repository/commons-lang/commons-lang/2.3/commons-lang-2.3.jar
[ERROR] urls[7] = file:/Users/rhusar/.m2/repository/org/apache/maven/enforcer/enforcer-api/1.3.1/enforcer-api-1.3.1.jar
[ERROR] urls[8] = file:/Users/rhusar/.m2/repository/org/apache/maven/enforcer/enforcer-rules/1.3.1/enforcer-rules-1.3.1.jar
[ERROR] urls[9] = file:/Users/rhusar/.m2/repository/org/apache/maven/shared/maven-common-artifact-filters/1.4/maven-common-artifact-filters-1.4.jar
[ERROR] urls[10] = file:/Users/rhusar/.m2/repository/org/beanshell/bsh/2.0b4/bsh-2.0b4.jar
[ERROR] urls[11] = file:/Users/rhusar/.m2/repository/org/apache/maven/shared/maven-dependency-tree/2.1/maven-dependency-tree-2.1.jar
[ERROR] urls[12] = file:/Users/rhusar/.m2/repository/org/codehaus/plexus/plexus-component-annotations/1.5.5/plexus-component-annotations-1.5.5.jar
[ERROR] urls[13] = file:/Users/rhusar/.m2/repository/org/eclipse/aether/aether-util/0.9.0.M2/aether-util-0.9.0.M2.jar
[ERROR] urls[14] = file:/Users/rhusar/.m2/repository/org/codehaus/plexus/plexus-i18n/1.0-beta-6/plexus-i18n-1.0-beta-6.jar
[ERROR] Number of foreign imports: 1
[ERROR] import: Entry[import  from realm ClassRealm[maven.api, parent: null]]
[ERROR]
[ERROR] -----------------------------------------------------
[ERROR] : begin 0, end 3, length 1
[ERROR] -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/PluginContainerException