dynalang version 0.4-1 failed to build on i386

dynalang version 0.4-1 failed to build on i386
Link to failed build: https://launchpad.net/ubuntu/+archive/test-rebuild-20110329/+buildjob/2391592

Direct link to the build log: https://launchpad.net/ubuntu/+archive/test-rebuild-20110329/+buildjob/2391592/+files/buildlog_ubuntu-natty-i386.dynalang_0.4-1_FAILEDTOBUILD.txt.gz

This log snippet might be of interest, since it triggered the matcher 'Purging chroot-autobuild'.
Excerpt 1493 lines into the build log:

 at java.lang.reflect.Method.invoke(Method.java:616)
 at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
 at org.apache.tools.ant.Task.perform(Task.java:348)
 at org.apache.tools.ant.Target.execute(Target.java:390)
 at org.apache.tools.ant.Target.performTasks(Target.java:411)
 at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1397)
 at org.apache.tools.ant.Project.executeTarget(Project.java:1366)
 at org.apache.tools.ant.helper.DefaultExecutor.executeTargets(DefaultExecutor.java:41)
 at org.apache.tools.ant.Project.executeTargets(Project.java:1249)
 at org.apache.tools.ant.Main.runBuild(Main.java:801)
 at org.apache.tools.ant.Main.startAnt(Main.java:218)
 at org.apache.tools.ant.Main.start(Main.java:180)
 at org.apache.tools.ant.Main.main(Main.java:269)
Caused by: java.lang.ClassNotFoundException: org.apache.tools.ant.taskdefs.optional.TraXLiaison
 at java.net.URLClassLoader$1.run(URLClassLoader.java:217)
 at java.security.AccessController.doPrivileged(Native Method)
 at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
 at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
 ... 21 more

Total time: 7 seconds
make: *** [debian/stamp-ant-build] Error 1
dpkg-buildpackage: error: debian/rules build gave error exit status 2
******************************************************************************
Build finished at 20110403-1057
FAILED [dpkg-buildpackage died]
Purging chroot-autobuild/build/buildd/dynalang-0.4