java.util.ConcurrentModificationException in Goal

maven:run-touchstone:
Trying to get missing dependencies (and updated snapshots) required by Touchstone:

• Checking for an update of touchstone:touchstone:SNAPSHOT:jar from http://people.apache.org/repo/m1-snapshot-repository/
  Skipping download as local copy is up to date!
• Checking for an update of touchstone:test:SNAPSHOT:war from http://people.apache.org/repo/m1-snapshot-repository/
  Skipping download as local copy is up to date!
  build:start:

clean:clean:
xdoc:clean:

[delete] Deleting directory /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target

clean:

java:prepare-filesystem:
[mkdir] Created dir: /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/classes

java:init:

java:compile:
[echo]
maven.dependency.classpath:
/export/home/continuum/.maven/repository/ant/jars/ant-optional-1.5.1.jar
/export/home/continuum/maven-1.1/lib/maven.jar
/export/home/continuum/.maven/repository/maven/jars/maven-model-3.0.1.jar
/export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/lib/a.jar
/export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/lib/b.jar
/export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/lib/c-1.0-alpha-1-SNAPSHOT.jar
/export/home/continuum/.maven/repository/classworlds/jars/classworlds-1.0-beta-1.jar
/export/home/continuum/.maven/repository/touchstone/jars/touchstone-SNAPSHOT.jar
/export/home/continuum/.maven/repository/commons-jelly/jars/commons-jelly-tags-interaction-1.0.jar

[echo] Compiling to /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/classes
[javac] Compiling 1 source file to /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/classes

java:jar-resources:
Copying 1 file to /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/classes
Copying 1 file to /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/classes/org/apache/maven/touchstone
Copying 2 files to /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/classes

test:test:
java:prepare-filesystem:

java:init:

java:compile:
[echo]
maven.dependency.classpath:
/export/home/continuum/.maven/repository/ant/jars/ant-optional-1.5.1.jar
/export/home/continuum/maven-1.1/lib/maven.jar
/export/home/continuum/.maven/repository/maven/jars/maven-model-3.0.1.jar
/export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/lib/a.jar
/export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/lib/b.jar
/export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/lib/c-1.0-alpha-1-SNAPSHOT.jar
/export/home/continuum/.maven/repository/classworlds/jars/classworlds-1.0-beta-1.jar
/export/home/continuum/.maven/repository/touchstone/jars/touchstone-SNAPSHOT.jar
/export/home/continuum/.maven/repository/commons-jelly/jars/commons-jelly-tags-interaction-1.0.jar

[echo] Compiling to /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/classes

java:jar-resources:

test:prepare-filesystem:
[mkdir] Created dir: /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/test-classes
[mkdir] Created dir: /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/test-reports

test:test-resources:
Copying 1 file to /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/test-classes/org/apache/maven/touchstone
Copying 1 file to /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/test-classes

test:compile:
[javac] Compiling 1 source file to /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/test-classes

jar:jar:
[jar] Building jar: /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/touchstone-1.0.jar

touchstone-tests:
xdoc:init-i18n:
[echo] Init the i18n support

xdoc:init:
[echo] Generates the directory structure required for xdocs
[mkdir] Created dir: /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/generated-xdocs
[mkdir] Created dir: /export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/target/docs

test-plugin-loading:
[echo] DEPRECATED: the use of dependency-handle is deprecated. Please use maven:get/set to modify properties of the multiproject plugin

touchstone-goal-A:
[echo] Overriding touchstone-goal-A

touchstone-goal-B:
[echo] touchstone-goal-B defined in plugin.

test-addPath:

test-plugin-property-override:
[echo] maven.touchstone.A = override.maven.touchstone.A

touchstone-goal-C:
[echo] preGoal for touchstone-goal-C is running ...
[echo] touchstone-goal-C defined in plugin.
Running post goal: touchstone-goal-C
[echo] postGoal for touchstone-goal-C is running ...

[echo] checkValue = true
touchstone-goal-D:
[echo] preGoal for touchstone-goal-D is running ...
touchstone-partner-goal-A:

-------------------------------------------------------------------------------
BUILD FAILED
-------------------------------------------------------------------------------
Errors stack :
>> Unable to obtain goal [maven:run-touchstone]
>> File...... file:/export/home/continuum/continuum_1.0.3_data/working-directory/6/maven.xml
>> Element... maven:maven
>> Line...... 38
>> Column.... 143
>> Unable to obtain goal [touchstone-tests]
>> File...... file:/export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/maven.xml
>> Element... attainGoal
>> Line...... 137
>> Column.... 43
>> Unable to obtain goal [touchstone-goal-D]
>> java.util.ConcurrentModificationException

Exception stack traces :
org.apache.maven.werkz.UnattainableGoalException: Unable to obtain goal [maven:run-touchstone]
at org.apache.maven.werkz.Goal.fire(Goal.java:698)
at org.apache.maven.werkz.Goal.attain(Goal.java:623)
at org.apache.maven.plugin.PluginManager.attainGoals(PluginManager.java:712)
at org.apache.maven.MavenSession.attainGoals(MavenSession.java:265)
at org.apache.maven.cli.App.doMain(App.java:306)
at org.apache.maven.cli.App.main(App.java:219)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at com.werken.forehead.Forehead.run(Forehead.java:551)
at com.werken.forehead.Forehead.main(Forehead.java:581)
Caused by: org.apache.commons.jelly.JellyTagException: file:/export/home/continuum/continuum_1.0.3_data/working-directory/6/maven.xml:38:143: Unable to obtain goal [touchstone-tests]
at org.apache.maven.jelly.tags.maven.MavenTag.doTag(MavenTag.java:103)
at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:250)
at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
at org.apache.maven.jelly.tags.werkz.MavenGoalTag.runBodyTag(MavenGoalTag.java:83)
at org.apache.maven.jelly.tags.werkz.MavenGoalTag$MavenGoalAction.performAction(MavenGoalTag.java:116)
at org.apache.maven.werkz.Goal.fire(Goal.java:691)
... 11 more
Caused by: org.apache.maven.werkz.UnattainableGoalException: Unable to obtain goal [touchstone-tests]
at org.apache.maven.werkz.Goal.fire(Goal.java:698)
at org.apache.maven.werkz.Goal.attain(Goal.java:623)
at org.apache.maven.plugin.PluginManager.attainGoals(PluginManager.java:712)
at org.apache.maven.MavenSession.attainGoals(MavenSession.java:265)
at org.apache.maven.jelly.tags.maven.MavenTag.doTag(MavenTag.java:83)
... 16 more
Caused by: org.apache.commons.jelly.JellyTagException: file:/export/home/continuum/continuum_1.0.3_data/working-directory/6/src/test/touchstone-build/maven.xml:137:43: Unable to obtain goal [touchstone-goal-D]
at org.apache.maven.jelly.tags.werkz.MavenAttainGoalTag.doTag(MavenAttainGoalTag.java:134)
at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:250)
at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
at org.apache.maven.jelly.tags.werkz.MavenGoalTag.runBodyTag(MavenGoalTag.java:83)
at org.apache.maven.jelly.tags.werkz.MavenGoalTag$MavenGoalAction.performAction(MavenGoalTag.java:116)
at org.apache.maven.werkz.Goal.fire(Goal.java:691)
... 20 more
Caused by: org.apache.maven.werkz.UnattainableGoalException: Unable to obtain goal [touchstone-goal-D]
at org.apache.maven.jelly.tags.werkz.MavenAttainGoalTag.doTag(MavenAttainGoalTag.java:133)
... 25 more
Caused by: java.util.ConcurrentModificationException
at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:448)
at java.util.AbstractList$Itr.next(AbstractList.java:419)
at org.apache.maven.werkz.Goal.firePreGoalCallbacks(Goal.java:743)
at org.apache.maven.werkz.Goal.fire(Goal.java:669)
at org.apache.maven.werkz.Goal.attain(Goal.java:623)
at org.apache.maven.werkz.WerkzProject.attainGoal(WerkzProject.java:209)
at org.apache.maven.jelly.tags.werkz.MavenAttainGoalTag.doTag(MavenAttainGoalTag.java:115)
... 25 more
-------------------------------------------------------------------------------
Total time : 1 minutes 19 seconds
Finished at : Friday, April 13, 2007 11:01:48 PM GMT+00:00
Final Memory : 8M/16M
-------------------------------------------------------------------------------