A posting on mlvm-dev:

http://mail.openjdk.java.net/pipermail/mlvm-dev/2011-September/003912.html

reports a VM crash that looks like:

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0xfe563edc, pid=29748, tid=20
#
# JRE version: 7.0-b147
# Java VM: Java HotSpot(TM) Server VM (21.0-b17 mixed mode solaris-x86 )
# Problematic frame:
# V  [libjvm.so+0x563edc]  bool ciKlass::is_subtype_of(ciKlass*)+0xe0
#
# Failed to write core dump. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again
#
# An error report file with more information is saved as:
# /home/ct232829/hsx/hotspot-comp/7055941/crash/hs_err_pid29748.log
[thread 21 also had an error]
#
# If you would like to submit a bug report, please visit:
#   http://bugreport.sun.com/bugreport/crash.jsp
#

Running with a debug VM results in:

==============================================================================
Unexpected Error
------------------------------------------------------------------------------
Internal Error at ciKlass.cpp:69, pid=29921, tid=21
assert(is_loaded() && that->is_loaded()) failed: must be loaded

Do you want to debug the problem?

To debug, run 'dbx - 29921'; then switch to thread 21
Enter 'yes' to launch dbx automatically (PATH must include dbx)
Otherwise, press RETURN to abort...
==============================================================================

(dbx) where
current thread: t@21
  [1] _waitid(0x0, 0x74e2, 0xb578e780, 0x3), at 0xfeecaf95 
  [2] _waitpid(0x74e2, 0xb578e844, 0x0), at 0xfee793bf 
  [3] waitpid(0x74e2, 0xb578e844, 0x0), at 0xfeebc805 
=>[4] os::fork_and_exec(cmd = 0xfed2578c "dbx - 29921"), line 6277 in "os_solaris.cpp"
  [5] VMError::show_message_box(this = 0xb578eae4, buf = 0xfed2578c "dbx - 29921", buflen = 2000), line 56 in "vmError_solaris.cpp"
  [6] VMError::report_and_die(this = 0xb578eae4), line 806 in "vmError.cpp"
  [7] report_vm_error(file = 0xfe77a65c "/home/ct232829/hsx/hotspot-comp/hotspot/src/share/vm/ci/ciKlass.cpp", line = 69, error_msg = 0xfe77a6a0 "assert(is_loaded() && that->is_loaded()) failed", detail_msg = 0xfe77a6d0 "must be loaded"), line 216 in "debug.cpp"
  [8] ciKlass::is_subtype_of(this = 0x8480c40, that = 0x8481178), line 69 in "ciKlass.cpp"
  [9] Parse::optimize_inlining(this = 0xb578f464, caller = 0x8483a30, bci = 1, klass = 0x8481178, dest_method = 0x8484098, receiver_type = 0x842503c), line 868 in "doCall.cpp"
  [10] Parse::do_call(this = 0xb578f464), line 419 in "doCall.cpp"
  [11] Parse::do_one_bytecode(this = 0xb578f464), line 2220 in "parse2.cpp"
  [12] Parse::do_one_block(this = 0xb578f464), line 1405 in "parse1.cpp"
  [13] Parse::do_all_blocks(this = 0xb578f464), line 680 in "parse1.cpp"
  [14] Parse::Parse(this = 0xb578f464, caller = 0x80c5298, parse_method = 0x8483a30, expected_uses = 6701.0), line 589 in "parse1.cpp"
  [15] ParseGenerator::generate(this = 0x83e8a80, jvms = 0x80c5298), line 85 in "callGenerator.cpp"
  [16] Parse::do_call(this = 0xb578fd9c), line 469 in "doCall.cpp"
  [17] Parse::do_one_bytecode(this = 0xb578fd9c), line 2220 in "parse2.cpp"
  [18] Parse::do_one_block(this = 0xb578fd9c), line 1405 in "parse1.cpp"
  [19] Parse::do_all_blocks(this = 0xb578fd9c), line 680 in "parse1.cpp"
  [20] Parse::Parse(this = 0xb578fd9c, caller = 0x8411280, parse_method = 0x847fa00, expected_uses = 10000.0), line 589 in "parse1.cpp"
  [21] ParseGenerator::generate(this = 0x83e85c0, jvms = 0x8411280), line 85 in "callGenerator.cpp"
  [22] Compile::Compile(this = 0xb5790540, ci_env = 0xb5790b50, compiler = 0x830f370, target = 0x847fa00, osr_bci = -1, subsume_loads = true, do_escape_analysis = true), line 685 in "compile.cpp"
  [23] C2Compiler::compile_method(this = 0x830f370, env = 0xb5790b50, target = 0x847fa00, entry_bci = -1), line 130 in "c2compiler.cpp"
  [24] CompileBroker::invoke_compiler_on_method(task = 0x8443080), line 1680 in "compileBroker.cpp"
  [25] CompileBroker::compiler_thread_loop(), line 1521 in "compileBroker.cpp"
  [26] compiler_thread_entry(thread = 0x8320800, __the_thread__ = 0x8320800), line 2971 in "thread.cpp"
  [27] JavaThread::thread_main_inner(this = 0x8320800), line 1503 in "thread.cpp"
  [28] JavaThread::run(this = 0x8320800), line 1487 in "thread.cpp"
  [29] java_start(thread_addr = 0x8320800), line 1067 in "os_solaris.cpp"
  [30] _thr_setup(0xfd749a00), at 0xfeec71d0 
  [31] _lwp_start(0x0, 0x74e2, 0xb578e780, 0x3, 0xfd749a00, 0xfef3e000), at 0xfeec74c0 
(dbx) fr 8
Current function is ciKlass::is_subtype_of
   69     assert(is_loaded() && that->is_loaded(), "must be loaded");
(dbx) p this->print()
<ciInstanceKlass name=NEW2 loader=0xe5e88000 loaded=true initialized=true finalized=false subklass=false size=16 flags=public,super super=java/lang/Object ident=714 PERM address=0x8480c40>this->print() = (void)
(dbx) p that->print() 
<ciInstanceKlass name=NEW2 loader=0x0 loaded=false ident=720  address=0x8481178>that->print() = (void)
(dbx) 

This is another incarnation of problems with method handle signatures and boot class path (like 6939196 or 7056328).