Build failure using IBM Java 6 SDK as host JVM on linux-ia32

I am trying to build jikes RVM, using the following command:
ant -Dhost.name=x86_64-linux -Dconfig.name=development

And it fails (for both jikes 3.0.1 and 3.1.0), using different versions of java.

build-bootimage:
[echo] Building bootimage. Output redirected to : /local/jikesrvm-3.0.1/target/development_x86_64-linux/BootImageWriterOutput.txt
[echo] MMTk properties = /local/jikesrvm-3.0.1/build/mmtk/default.properties
[java] BootImageWriter: compiler arg: O2
[java] Java Result: 1
[echo] BootImageWriter: starting up
[echo] BootImageCompiler: init (opt compiler)
[echo] BootImageWriter: loading
[echo] java.lang.NoClassDefFoundError: java.util.Collections$2
[echo] at org.jikesrvm.classloader.BootstrapClassLoader.loadVMClass(BootstrapClassLoader.java:133)
[echo] at org.jikesrvm.classloader.TypeReference.resolveInternal(TypeReference.java:788)
[echo] at org.jikesrvm.classloader.TypeReference.resolve(TypeReference.java:762)
[echo] at org.jikesrvm.tools.bootImageWriter.BootImageWriter.createBootImageObjects(BootImageWriter.java:1300)
[echo] at org.jikesrvm.tools.bootImageWriter.BootImageWriter.main(BootImageWriter.java:897)
[echo] Caused by: java.lang.VerifyError: java.util.Collections$ReverseComparator
[echo] at com.ibm.oti.vm.VM.findClassOrNull(Native Method)
[echo] at com.ibm.oti.vm.BootstrapClassLoader.loadClass(BootstrapClassLoader.java:62)
[echo] at java.lang.Class.forNameImpl(Native Method)
[echo] at java.lang.Class.forName(Class.java:169)
[echo] at org.jikesrvm.classloader.RVMType.createClassForType(RVMType.java:565)
[echo] at org.jikesrvm.classloader.RVMType.<init>(RVMType.java:259)
[echo] at org.jikesrvm.classloader.RVMClass.<init>(RVMClass.java:1176)
[echo] at org.jikesrvm.classloader.RVMClass.readClass(RVMClass.java:1545)
[echo] at org.jikesrvm.classloader.RVMClassLoader.defineClassInternal(RVMClassLoader.java:336)
[echo] at org.jikesrvm.classloader.BootstrapClassLoader.loadVMClass(BootstrapClassLoader.java:120)
[echo] ... 4 more
[echo] Exception in thread "main" java.lang.Error:
[echo] BootImageWriter: /local/jikesrvm-3.0.1/target/development_x86_64-linux/Primordials.txt contains a class named "Ljava/util/Collections$2;", but we can't find a class with that name: java.lang.NoClassDefFoundError: java.util.Collections$2
[echo] at org.jikesrvm.tools.bootImageWriter.BootImageWriterMessages.fail(BootImageWriterMessages.java:26)
[echo] at org.jikesrvm.tools.bootImageWriter.BootImageWriter.createBootImageObjects(BootImageWriter.java:1303)
[echo] at org.jikesrvm.tools.bootImageWriter.BootImageWriter.main(BootImageWriter.java:897)

BUILD FAILED
/local/nvk/t/jikesrvm-3.0.1/build.xml:1418: The following error occurred while executing this line:
/local/nvk/t/jikesrvm-3.0.1/build.xml:1427: Failed to write bootimage.

Total time: 2 minutes 0 seconds
--------------------------
This must be something straight forward (I hope). Can someone point at what I am missing?