Index: VTK/Common/vtkFunctionParser.cxx
===================================================================
RCS file: /cvsroot/ParaView3/ParaView3/VTK/Common/vtkFunctionParser.cxx,v
retrieving revision 1.46
diff -u -3 -p -r1.46 vtkFunctionParser.cxx
--- VTK/Common/vtkFunctionParser.cxx	6 Apr 2010 14:34:07 -0000	1.46
+++ VTK/Common/vtkFunctionParser.cxx	13 Apr 2010 20:18:52 -0000
@@ -534,8 +534,7 @@ bool vtkFunctionParser::Evaluate()
   
   this->StackPointer = -1;
 
-  if (this->FunctionMTime.GetMTime() > this->ParseMTime.GetMTime() ||
-    this->VariableMTime.GetMTime() > this->ParseMTime.GetMTime())
+  if (this->FunctionMTime.GetMTime() > this->ParseMTime.GetMTime())
     {
     if (this->Parse() == 0)
       {
Index: Servers/Filters/vtkPVArrayCalculator.cxx
===================================================================
RCS file: /cvsroot/ParaView3/ParaView3/Servers/Filters/vtkPVArrayCalculator.cxx,v
retrieving revision 1.5
diff -u -3 -p -r1.5 vtkPVArrayCalculator.cxx
--- Servers/Filters/vtkPVArrayCalculator.cxx	9 Apr 2010 13:55:50 -0000	1.5
+++ Servers/Filters/vtkPVArrayCalculator.cxx	13 Apr 2010 20:18:52 -0000
@@ -14,14 +14,15 @@
 =========================================================================*/
 #include "vtkPVArrayCalculator.h"
 
-#include "vtkGraph.h"
-#include "vtkDataSet.h"
 #include "vtkCellData.h"
-#include "vtkPointData.h"
 #include "vtkDataObject.h"
+#include "vtkDataSet.h"
+#include "vtkFunctionParser.h"
+#include "vtkGraph.h"
 #include "vtkInformation.h"
-#include "vtkObjectFactory.h"
 #include "vtkInformationVector.h"
+#include "vtkObjectFactory.h"
+#include "vtkPointData.h"
 
 #include <vtksys/ios/sstream>
 #include <assert.h>
@@ -50,6 +51,10 @@ void vtkPVArrayCalculator::UpdateArrayAn
   // It's safe to call these methods in RequestData() since they don't call
   // this->Modified().
   this->RemoveAllVariables();
+
+  // This ensures that the vtkFunctionParser re-evalutes the expression.
+  this->FunctionParser->SetFunction(0);
+  this->FunctionParser->SetFunction(this->Function);
   
   // Add coordinate scalar and vector variables
   this->AddCoordinateScalarVariable( "coordsX", 0 );