We are currently using Hudson version 1.319 to build our Maven projects. This
is the latest up date and before this update was applied our builds were
completing without a problem. Since updating, we get broken builds quite
regularly and the console log reports the following:

Started by upstream project "<our project name>" build number 238
Building on master
FATAL: null
java.lang.NullPointerException
at hudson.maven.MavenBuild$RunnerImpl.decideWorkspace
(MavenBuild.java:481)
at hudson.model.AbstractBuild$AbstractRunner.run(AbstractBuild.java:334)
at hudson.model.Run.run(Run.java:1090)
at hudson.maven.MavenBuild.run(MavenBuild.java:207)
at hudson.model.ResourceController.execute(ResourceController.java:93)
at hudson.model.Executor.run(Executor.java:122)

We are using Maven 2.1.0. The system properties as reported by Hudson are:

awt.toolkit sun.awt.windows.WToolkit
executable-war C:\Program Files\Hudson\hudson.war
file.encoding Cp1252
file.encoding.pkg sun.io
file.separator \
hudson.diyChunking true
java.awt.graphicsenv sun.awt.Win32GraphicsEnvironment
java.awt.headless true
java.awt.printerjob sun.awt.windows.WPrinterJob
java.class.path hudson.war
java.class.version 50.0
java.endorsed.dirs C:\Program Files\Java\jre6\lib\endorsed
java.ext.dirs C:\Program Files\Java\jre6\lib\ext;C:\WINDOWS\Sun\Java\lib\ext
java.home C:\Program Files\Java\jre6
java.io.tmpdir C:\DOCUME~1\DEVSER~1\LOCALS~1\Temp\
java.library.path
C:\WINDOWS\system32;.;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\
PHP\;C:\Program Files\Windows Resource Kits\Tools\;C:\oracle\product\10.2.0\db_1
\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\Program
Files\Microsoft SQL Server\80\Tools\Binn\;C:\Program Files\Borland\StarTeam SDK
2005 R2\Lib;C:\Program Files\Borland\StarTeam SDK 2005 R2
\Bin;C:\www\openssl\bin;C:\www\Apache22\bin;C:\www\php5;C:\www\mysql5
\bin;C:\www\perl\bin;C:\www\tomcat5\bin;C:\PHP;C:\Program Files\Common
Files\GTK\2.0\bin;C:\Maven\apache-maven-2.2.0\bin;C:\Program
Files\NSIS;C:\Program Files\exe4j\bin;C:\Program Files\SlikSvn\bin\;C:\Program
Files\TortoiseSVN\bin;C:\Program Files\MySQL\MySQL Server 5.0\bin
java.runtime.name Java(TM) SE Runtime Environment
java.runtime.version 1.6.0_12-b04
java.specification.name Java Platform API Specification
java.specification.vendor Sun Microsystems Inc.
java.specification.version 1.6
java.vendor Sun Microsystems Inc.
java.vendor.url http://java.sun.com/
java.vendor.url.bug http://java.sun.com/cgi-bin/bugreport.cgi
java.version 1.6.0_12
java.vm.info mixed mode, sharing
java.vm.name Java HotSpot(TM) Client VM
java.vm.specification.name Java Virtual Machine Specification
java.vm.specification.vendor Sun Microsystems Inc.
java.vm.specification.version 1.0
java.vm.vendor Sun Microsystems Inc.
java.vm.version 11.2-b01
line.separator
os.arch x86
os.name Windows XP
os.version 5.1
path.separator ;
sun.arch.data.model 32
sun.boot.class.path C:\Program Files\Java\jre6\lib\resources.jar;C:\Program
Files\Java\jre6\lib\rt.jar;C:\Program Files\Java\jre6
\lib\sunrsasign.jar;C:\Program Files\Java\jre6\lib\jsse.jar;C:\Program
Files\Java\jre6\lib\jce.jar;C:\Program Files\Java\jre6
\lib\charsets.jar;C:\Program Files\Java\jre6\classes
sun.boot.library.path C:\Program Files\Java\jre6\bin
sun.cpu.endian little
sun.cpu.isalist
sun.desktop windows
sun.io.unicode.encoding UnicodeLittle
sun.java.launcher SUN_STANDARD
sun.jnu.encoding Cp1252
sun.management.compiler HotSpot Client Compiler
sun.os.patch.level Service Pack 3
svnkit.ssh2.persistent false
user.country US
user.dir C:\Program Files\Hudson
user.home C:\Documents and Settings\DEVSERVER
user.language en
user.name DEVSERVER
user.timezone Europe/Berlin
user.variant