VCSVersionReader returns an illegal null on Remote Agent

2008-01-22 17:12:06,715 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [BuildAgentControllerImpl] Agent 'Remote Agent on scharers.sydney.atlassian.com' ready to take build from queue...
2008-01-22 17:12:06,716 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [JmsSelectorUtils] allowableSelector: allowableAgents LIKE '%[491521]%'
2008-01-22 17:13:40,636 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [AgentQueueAccessorImpl] TEST-DEF-16 taken from queue.
2008-01-22 17:13:41,064 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [BuildAgentControllerImpl] Build TEST-DEF-16 started building on agent Remote Agent on scharers.sydney.atlassian.com
2008-01-22 17:13:41,064 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [DefaultBuildAgent] Running build task: com.atlassian.bamboo.v2.build.task.CheckoutUpdateForBuild
2008-01-22 17:13:41,174 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [CheckoutUpdateForBuild] Updating source code to revision: 51905
2008-01-22 17:13:41,187 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [SvnRepository] Source found at  '/Users/ahempel/bamboo-homes/agent/xml-data/build-dir/TEST-DEF'. Updating source...
2008-01-22 17:13:46,927 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [UpdateEventHandler]           
2008-01-22 17:13:47,009 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [UpdateEventHandler] At revision 51905
2008-01-22 17:13:48,108 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [CheckoutUpdateForBuild] Updated source code to revision: 51905
2008-01-22 17:13:48,108 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [DefaultBuildAgent] Running build task: com.atlassian.bamboo.build.pipeline.tasks.PrepareBuildTask
2008-01-22 17:13:48,251 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [PrepareBuildTask] Executing build TEST-DEF-16
2008-01-22 17:13:48,414 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [PrepareBuildTask] Runnning pre-build action: com.atlassian.bamboo.vcsversion.VCSVersionReader@d6cc5e
2008-01-22 17:13:48,481 WARN [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [PrepareBuildTask] Exception occurred while executing custom pre-build action 'com.atlassian.bamboo.vcsversion.VCSVersionReader@d6cc5e'. Building will abort...
java.lang.IllegalStateException: @NotNull method com/atlassian/bamboo/vcsversion/VCSVersionReader.call must not return null
	at com.atlassian.bamboo.vcsversion.VCSVersionReader.call(VCSVersionReader.java)
	at com.atlassian.bamboo.build.pipeline.tasks.PrepareBuildTask.call(PrepareBuildTask.java:53)
	at com.atlassian.bamboo.v2.build.agent.DefaultBuildAgent.build(DefaultBuildAgent.java:144)
	at com.atlassian.bamboo.v2.build.agent.BuildAgentControllerImpl.performBuild(BuildAgentControllerImpl.java:63)
	at com.atlassian.bamboo.v2.build.agent.DefaultBuildAgent$1.run(DefaultBuildAgent.java:85)
	at com.atlassian.bamboo.build.pipeline.concurrent.NamedThreadFactory$1.run(NamedThreadFactory.java:32)
	at edu.emory.mathcs.backport.java.util.concurrent.helpers.ThreadHelpers$1.run(ThreadHelpers.java:34)
	at java.lang.Thread.run(Thread.java:613)

2008-01-22 17:13:48,482 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [DefaultBuildAgent] Running build task: com.atlassian.bamboo.build.pipeline.tasks.ExecuteBuildTask
2008-01-22 17:13:48,701 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [AbstractBuilder] Starting to build 'Test - Default'<br /> ... running command line: /opt/maven-2/bin/mvn clean test clover:instrument clover:clover<br /> ... in : /Users/ahempel/bamboo-homes/agent/xml-data/build-dir/TEST-DEF<br /> ... using java: /System/Library/Frameworks/JavaVM.framework/Versions/1.5.0/Home<br /> ... using environment variables: 
2008-01-22 17:13:52,724 INFO [TEST-DEF:Error Pump] [ErrorStreamToLogsPumper] Clover Version 1.3.14, built on August 01 2007
2008-01-22 17:13:52,731 INFO [TEST-DEF:Error Pump] [ErrorStreamToLogsPumper] loaded from: /Users/ahempel/.m2/repository/com/cenqua/clover/clover/1.3.14/clover-1.3.14.jar
2008-01-22 17:13:52,750 INFO [TEST-DEF:Error Pump] [ErrorStreamToLogsPumper] 30 Seat Team License registered to mike@atlassian.com, Atlassian
2008-01-22 17:13:52,757 INFO [TEST-DEF:Error Pump] [ErrorStreamToLogsPumper] No coverage database '/Users/ahempel/bamboo-homes/agent/xml-data/build-dir/TEST-DEF/target/clover/clover.db' found. Creating a fresh one.
2008-01-22 17:13:52,765 INFO [TEST-DEF:Error Pump] [ErrorStreamToLogsPumper] Processing files at 1.4 source level.
2008-01-22 17:13:52,855 INFO [TEST-DEF:Error Pump] [ErrorStreamToLogsPumper] Instrumented 1 source files.
2008-01-22 17:13:55,300 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [AbstractBuilder] Build process for 'Test - Default' returned with return code = 0
2008-01-22 17:13:56,062 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [ExecuteBuildTask] Running post build plugin 'Clover Results Collector'
2008-01-22 17:13:56,562 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [ExecuteBuildTask] Running post build plugin 'Artifact Copier'
2008-01-22 17:13:56,643 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [BuildArtifactPostProcessor] Copying the build artifacts for build:TEST-DEF-16
2008-01-22 17:15:01,029 INFO [BAM::Remote Agent on scharers.sydney.atlassian.com::Agent] [RemoteBuildResultProcessor] Build TEST-DEF-16 completed on Bamboo agent. Sending results to server.