--- a/src/JavaVM.st	Wed Nov 16 13:33:38 2011 +0000
+++ b/src/JavaVM.st	Wed Nov 16 14:39:06 2011 +0000
@@ -1601,6 +1601,7 @@
     WaitTable := IdentityDictionary new.
     WaitTableAccess := Semaphore "RecursionLock" forMutualExclusion.
     WaitTableAccess name: 'JavaVM wait table access mutex'.
+    Logger log: 'Clearing EnteredMonitorsPerProcess' severity:#info facility:#JVM.
     EnteredMonitorsPerProcess := IdentityDictionary new.
     self initializePrimitiveClasses.
     self initializeOpenFileTable.
@@ -2009,8 +2010,12 @@
     WaitTable := IdentityDictionary new.
     WaitTableAccess := Semaphore "RecursionLock" forMutualExclusion.
     WaitTableAccess name: 'JavaVM wait table access mutex'.
-    EnteredMonitorsPerProcess size > 0 ifTrue: [ self breakPoint: #mh ].
+    EnteredMonitorsPerProcess notNil ifTrue: [
+        EnteredMonitorsPerProcess 
+            keysAndValuesDo: [:p :value | value size > 0 ifTrue: [ self breakPoint: #mh ] ]
+    ].
     self releaseLeftOverMonitors.
+    Logger log: 'Clearing EnteredMonitorsPerProcess' severity:#info facility:#JVM.
     EnteredMonitorsPerProcess := IdentityDictionary new.
 
     "
@@ -2019,7 +2024,7 @@
     "Created: / 02-01-1998 / 18:04:05 / cg"
     "Modified: / 07-01-1998 / 22:58:10 / cg"
     "Modified: / 25-10-2010 / 19:14:51 / Jan Vrany <jan.vrany@fit.cvut.cz>"
-    "Modified: / 16-11-2011 / 14:26:05 / Marcel Hlopko <hlopkmar@fel.cvut.cz>"
+    "Modified: / 16-11-2011 / 15:02:48 / Marcel Hlopko <hlopkmar@fel.cvut.cz>"
 !
 
 releaseAllStreams
@@ -16034,6 +16039,15 @@
     "Created: / 8.1.1999 / 14:02:02 / cg"
 !
 
+enteredMonitorsOfProcessAt: aProcess 
+    "does not create empty collection like enteredMonitorsOfProcess"
+    
+    ^ EnteredMonitorsPerProcess at: aProcess ifAbsent: nil.
+
+    "Created: / 08-01-1999 / 14:02:02 / cg"
+    "Created: / 16-11-2011 / 15:37:58 / Marcel Hlopko <hlopkmar@fel.cvut.cz>"
+!
+
 monitorEnter: someObject in: aJavaContext 
     | mon  thisProcess  objString |
     self assert: (aJavaContext isJavaContext).
@@ -16064,7 +16078,7 @@
 !
 
 monitorExit: someObject in: aJavaContext 
-    | mon  thisProcess  wasBlocked  lastMon  objString |
+    | mon  thisProcess  wasBlocked  lastMon  objString enteredMonitors |
     self assert: (aJavaContext isJavaContext).
     someObject isNil ifTrue: [
         self throwNullPointerException.
@@ -16092,10 +16106,12 @@
             severity: #info
             facility: #JVM.
     ].
-    lastMon := (self enteredMonitorsOfProcess: thisProcess) removeLast.
+    enteredMonitors := self enteredMonitorsOfProcessAt: thisProcess.
+    enteredMonitors notNil ifTrue: [
+    lastMon := enteredMonitors removeLast.
     lastMon ~~ someObject ifTrue: [
         self halt: 'oops - monitor enter/exit nesting wrong'
-    ].
+    ]] ifFalse: [Logger log: ('Seems that monitors of %1 were already released' bindWith: thisProcess) severity:#info facility:#JVM].
     wasBlocked := OperatingSystem blockInterrupts.
      "mon count == 0 ifTrue: [ LeftMonitorObject := someObject ]."
     wasBlocked ifFalse: [ OperatingSystem unblockInterrupts ]
@@ -16167,6 +16183,7 @@
      (such an exception in native method)"
     
     | monitors |
+    self breakPoint:#mh.
     monitors := EnteredMonitorsPerProcess at: aProcess ifAbsent: nil.
     monitors notNil ifTrue: [
         monitors do: [
@@ -16184,12 +16201,11 @@
                 ].
             ].
         ].
-        EnteredMonitorsPerProcess removeKey: aProcess
-        .
+        EnteredMonitorsPerProcess removeKey: aProcess.
     ].
 
     "Created: / 04-11-2011 / 22:15:06 / Jan Vrany <jan.vrany@fit.cvut.cz>"
-    "Modified: / 08-11-2011 / 15:07:43 / Marcel Hlopko <hlopkmar@fel.cvut.cz>"
+    "Modified: / 16-11-2011 / 15:09:14 / Marcel Hlopko <hlopkmar@fel.cvut.cz>"
 !
 
 releaseSemaphoreFor:someObject