The following crash happened during Libraries 6 testing for jdk 6u24-rev-b00-2011-02-18:

#
# A fatal error has been detected by the Java Runtime Environment:
#
# SIGSEGV (0xb) at pc=0xfe6fdf07, pid=18092, tid=2
#
# JRE version: 6.0_24
# Java VM: Java HotSpot(TM) Client VM (19.1-b04 mixed mode, sharing solaris-x86 )
# Problematic frame:
# V [libjvm.so+0xfdf07]
#
# If you would like to submit a bug report, please visit:
# http://java.sun.com/webapps/bugreport/crash.jsp
#


The hs and java files are attached.

Looks like the problem anywhere in the working with file system. See some extract from native and java stack below:

Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0xfdf07]
V [libjvm.so+0xfdee2]
V [libjvm.so+0x23785b]
v ~RuntimeStub::throw_class_cast_exception Runtime1 stub
J com.sun.tools.javac.zip.ZipFileIndexEntry.compareTo(Ljava/lang/Object;)I
j java.util.Arrays.sort([Ljava/lang/Object;)V+17

Java frames: (J=compiled Java code, j=interpreted, Vv=VM code)
v ~RuntimeStub::throw_class_cast_exception Runtime1 stub
J com.sun.tools.javac.zip.ZipFileIndexEntry.compareTo(Ljava/lang/Object;)I
J java.util.Arrays.mergeSort([Ljava/lang/Object;[Ljava/lang/Object;III)V
J java.util.Arrays.mergeSort([Ljava/lang/Object;[Ljava/lang/Object;III)V

The problem was reproducible 3 times. It was reproducible with jdk 1.6.0_24 rev b23 as well.
Not a regression.
See comments for more info.