Most serviceability tools from 6u3 b01 (except jstack) cannot be used on 6u3 b01 process:

$ /set/vmsqe/jdk-builds/6/latest/solaris-amd64/bin/jmap 29386
Attaching to process ID 29386, please wait...
Exception in thread "main" java.lang.reflect.InvocationTargetException
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at sun.tools.jmap.JMap.runTool(JMap.java:178)
        at sun.tools.jmap.JMap.main(JMap.java:110)
Caused by: sun.jvm.hotspot.runtime.VMVersionMismatchException: Supported versions are 1.7.0. Target VM is 1.6.0_03-ea-b01
        at sun.jvm.hotspot.runtime.VM.checkVMVersion(VM.java:222)
        at sun.jvm.hotspot.runtime.VM.<init>(VM.java:275)
        at sun.jvm.hotspot.runtime.VM.initialize(VM.java:328)
        at sun.jvm.hotspot.bugspot.BugSpotAgent.setupVM(BugSpotAgent.java:594)
        at sun.jvm.hotspot.bugspot.BugSpotAgent.go(BugSpotAgent.java:494)
        at sun.jvm.hotspot.bugspot.BugSpotAgent.attach(BugSpotAgent.java:332)
        at sun.jvm.hotspot.tools.Tool.start(Tool.java:163)
        at sun.jvm.hotspot.tools.HeapSummary.main(HeapSummary.java:39)
        ... 6 more
This also affects "jstack -F" (in this case SA is used)