Running jhat on a heap dump generated from Java 1.5 results in an exception. Due to the size of the heap.bin file I haven't attached them to this bug report, it can be found at jurassic:/home/alanbur/jhat_crash.tar.bz2 - please pull it from there and let me know so I can delete the file

Version of JVM used to create heap.dump:
java version "1.5.0_07"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_07-b03)
Java HotSpot(TM) Server VM (build 1.5.0_07-b03, mixed mode)

Versison of jhat:
java version "1.6.0-rc"
Java(TM) SE Runtime Environment (build 1.6.0-rc-b102)
Java HotSpot(TM) Server VM (build 1.6.0-rc-b102, mixed mode)

Diagnostic message:
$ /usr/java/bin/jhat -J-Xmx2500m -stack false heap.bin
Reading from heap.bin...
Dump file created Thu Oct 19 09:00:55 PDT 2006
java.io.IOException: Unrecognized heap dump sub-record type: 0
        at com.sun.tools.hat.internal.parser.HprofReader.readHeapDump(HprofReader.java:485)
        at com.sun.tools.hat.internal.parser.HprofReader.read(HprofReader.java:222)
        at com.sun.tools.hat.internal.parser.Reader.readFile(Reader.java:79)
        at com.sun.tools.hat.Main.main(Main.java:143)