Index: source/core/inc/interpre.hxx
===================================================================
--- source/core/inc/interpre.hxx	(revision 269987)
+++ source/core/inc/interpre.hxx	(working copy)
@@ -660,6 +660,7 @@
 void ScBadName();
 // Statistik:
 double phi(double x);
+double integralPhi(double x);
 double taylor(double* pPolynom, USHORT nMax, double x);
 double gauss(double x);
 double gaussinv(double x);
Index: source/core/tool/interpr3.cxx
===================================================================
--- source/core/tool/interpr3.cxx	(revision 269987)
+++ source/core/tool/interpr3.cxx	(working copy)
@@ -209,6 +209,11 @@
     return  0.39894228040143268 * exp(-(x * x) / 2.0);
 }
 
+double ScInterpreter::integralPhi(double x)
+{ // Using gauss(x)+0.5 has severe cancellation errors for x<-4
+    return 0.5 * ::rtl::math::erfc(-x * 0.7071067811865475); // * 1/sqrt(2)
+}
+
 double ScInterpreter::taylor(double* pPolynom, USHORT nMax, double x)
 {
     RTL_LOGFILE_CONTEXT_AUTHOR( aLogger, "sc", "Eike.Rathke@sun.com", "ScInterpreter::taylor" );
@@ -1499,46 +1504,59 @@
 void ScInterpreter::ScNormDist()
 {
     RTL_LOGFILE_CONTEXT_AUTHOR( aLogger, "sc", "Eike.Rathke@sun.com", "ScInterpreter::ScNormDist" );
-    if ( MustHaveParamCount( GetByte(), 4 ) )
+    BYTE nParamCount = GetByte();
+    if ( !MustHaveParamCount( nParamCount, 3, 4))
+        return;
+    bool bCumulative = nParamCount == 4 ? GetBool() : true;
+    double sigma = GetDouble();                 // standard deviation
+    double mue = GetDouble();                   // mean
+    double x = GetDouble();                     // x
+    if (sigma <= 0.0)
     {
-        double kum = GetDouble();                   // 0 oder 1
-        double sigma = GetDouble();                 // Stdabw
-        double mue = GetDouble();                   // Mittelwert
-        double x = GetDouble();                     // x
-        if (sigma < 0.0)
-            PushError( errIllegalArgument);
-        else if (sigma == 0.0)
-            PushError( errDivisionByZero);
-        else if (kum == 0.0)                        // Dichte
-            PushDouble(phi((x-mue)/sigma)/sigma);
-        else                                        // Verteilung
-            PushDouble(0.5 + gauss((x-mue)/sigma));
+        PushIllegalArgument();
+        return;
     }
+    if (bCumulative)
+        PushDouble(integralPhi((x-mue)/sigma));
+    else
+        PushDouble(phi((x-mue)/sigma)/sigma);
 }
 
-void ScInterpreter::ScLogNormDist()
+void ScInterpreter::ScLogNormDist() //expanded, see #i100119#
 {
     RTL_LOGFILE_CONTEXT_AUTHOR( aLogger, "sc", "Eike.Rathke@sun.com", "ScInterpreter::ScLogNormDist" );
-    if ( MustHaveParamCount( GetByte(), 3 ) )
+    BYTE nParamCount = GetByte();
+    if ( !MustHaveParamCount( nParamCount, 1, 4)) 
+        return;
+    bool bCumulative = nParamCount == 4 ? GetBool() : true; // cumulative
+    double sigma = nParamCount >= 3 ? GetDouble() : 1.0; // standard deviation
+    double mue = nParamCount >= 2 ? GetDouble() : 0.0;   // mean
+    double x = GetDouble();                              // x
+    if (sigma <= 0.0)
     {
-        double sigma = GetDouble();                 // Stdabw
-        double mue = GetDouble();                   // Mittelwert
-        double x = GetDouble();                     // x
-        if (sigma < 0.0)
-            PushError( errIllegalArgument);
-        else if (sigma == 0.0)
-            PushError( errDivisionByZero);
-        else if (x <= 0.0)
+        PushIllegalArgument();
+        return;
+    }
+    if (bCumulative)
+    { // cumulative
+        if (x <= 0.0)
+            PushDouble(0.0);
+        else
+            PushDouble(integralPhi((log(x)-mue)/sigma));
+    }
+    else
+    { // density
+        if (x <= 0.0)
             PushIllegalArgument();
         else
-            PushDouble(0.5 + gauss((log(x)-mue)/sigma));
+            PushDouble(phi((log(x)-mue)/sigma)/sigma/x);
     }
 }
 
 void ScInterpreter::ScStdNormDist()
 {
     RTL_LOGFILE_CONTEXT_AUTHOR( aLogger, "sc", "Eike.Rathke@sun.com", "ScInterpreter::ScStdNormDist" );
-    PushDouble(0.5 + gauss(GetDouble()));
+    PushDouble(integralPhi(GetDouble()));
 }
 
 void ScInterpreter::ScExpDist()
Index: source/filter/excel/xeformula.cxx
===================================================================
--- source/filter/excel/xeformula.cxx	(revision 269987)
+++ source/filter/excel/xeformula.cxx	(working copy)
@@ -1813,6 +1813,35 @@
             }
         break;
 
+        case ocNormDist:
+            if( nParamCount == 3 )
+            {
+                // NORMDIST function needs 4 parameters in Excel
+                PrepareParam( rFuncData );
+                AppendBoolToken( true );
+                FinishParam( rFuncData );
+            }
+        break;
+
+        case ocLogNormDist:
+            switch( nParamCount )
+             {
+                //LOGNORMSIST function needs 3 parameters in Excel
+                case 1:
+                    PrepareParam( rFuncData );
+                    AppendIntToken( 0 );
+                    FinishParam( rFuncData );
+                 // do not break, add next default parameter
+                case 2:
+                    PrepareParam( rFuncData );
+                    AppendIntToken( 1 );
+                    FinishParam( rFuncData );
+                    break;
+                default:;
+             } 
+
+        break;
+
         default:;
     }
 }
Index: source/ui/src/scfuncs.src
===================================================================
--- source/ui/src/scfuncs.src	(revision 269987)
+++ source/ui/src/scfuncs.src	(working copy)
@@ -5718,7 +5718,7 @@
             0;
 			ID_FUNCTION_GRP_STATISTIC;
 			U2S( HID_FUNC_NORMVERT );
-			4;	0;	0;	0;	0;
+			4;	0;	0;	0;	1;
             0;
 		};
 		String 2 // Name of Parameter 1
@@ -5731,7 +5731,7 @@
 		};
 		String 4 // Name of Parameter 2
 		{
-			Text [ en-US ] = "mean" ;
+			Text [ en-US ] = "Mean" ;
 		};
 		String 5 // Description of Parameter 2
 		{
@@ -5751,7 +5751,7 @@
 		};
 		String 9 // Description of Parameter 4
 		{
-			Text [ en-US ] = "Cumulated. C=0 calculates the density function, C=1 the distribution." ;
+			Text [ en-US ] = "0 or FALSE calculates the probability density function. Any other value or TRUE or omitted calculates the cumulative distribution function." ;
 		};
 	};
 	 // -=*# Resource for function NORMINV #*=-
@@ -5854,7 +5854,7 @@
             0;
 			ID_FUNCTION_GRP_STATISTIC;
 			U2S( HID_FUNC_LOGNORMVERT );
-			3;	0;	0;	0;
+			4;	0;	1;	1;  1;
             0;
 		};
 		String 2 // Name of Parameter 1
@@ -5871,7 +5871,7 @@
 		};
 		String 5 // Description of Parameter 2
 		{
-			Text [ en-US ] = "Mean value. The mean value of the log normal distribution." ;
+			Text [ en-US ] = "The mean value of the log normal distribution. It is set to 0 if omitted." ;
 		};
 		String 6 // Name of Parameter 3
 		{
@@ -5879,8 +5879,16 @@
 		};
 		String 7 // Description of Parameter 3
 		{
-			Text [ en-US ] = "Standard deviation. The standard deviation of the log normal distribution." ;
+			Text [ en-US ] = "The standard deviation of the log normal distribution. It is set to 1 if omitted." ;
 		};
+        String 8 // Name of Parameter 4
+        {
+            Text [ en-US] = "Cumulative";
+        };
+        String 9 // Description of Parameter 4
+        {
+            Text [ en-US] = "0 or FALSE calculates the probability density function. Any other value or TRUE or omitted calculates the cumulative distribution function." ;
+        };
 	};
 	 // -=*# Resource for function LOGINV #*=-
 	Resource SC_OPCODE_LOG_INV