I have exactly the same problem when running no debug mode.
Here it is what I got.
Unhandled exception
Type=GPF vmState=0xffffffff
Target=20030915 (Windows XP 5.1 build 2600 Service Pack 1 x86)
ExceptionCode=0xc0000005 ExceptionAddress=0x1060b16b ContextFlags=0x0001003f
Handler1=0x111016c0 Handler2=0x10019730
Module=C:\Program Files\IBM\WebSphere Studio\Application Developer\v5.1.2\runtimes\base_v51\java\jre\bin\J9GC21.dll
Module_base_address=0x10600000
Offset_in_DLL=0x0000b16b
EDI=0x000a0c1c ESI=0x09ad2554 EAX=0x080246f8
EBX=0x00099a10 ECX=0x00099aac EDX=0x00000000
EBP=0x000cbf00 ESP=0x0481f9bc EIP=0x1060b16b
Generating crash dump: C:\Documents and Settings\patrick\j9.dmp
Thread: Servlet.Engine.Transports : 0 (priority 5) (daemon) (LOCATION OF ......