diff --git a/src/core/qgscoordinatetransform.cpp b/src/core/qgscoordinatetransform.cpp
index 814e5dfbd316..9cdde766f76e 100644
--- a/src/core/qgscoordinatetransform.cpp
+++ b/src/core/qgscoordinatetransform.cpp
@@ -42,6 +42,8 @@ QgsCoordinateTransform::QgsCoordinateTransform()
     , mInitialisedFlag( false )
     , mSourceProjection( 0 )
     , mDestinationProjection( 0 )
+    , mSourceDatumTransform( -1 )
+    , mDestinationDatumTransform( -1 )
 {
   setFinder();
 }
@@ -51,6 +53,8 @@ QgsCoordinateTransform::QgsCoordinateTransform( const QgsCoordinateReferenceSyst
     , mInitialisedFlag( false )
     , mSourceProjection( 0 )
     , mDestinationProjection( 0 )
+    , mSourceDatumTransform( -1 )
+    , mDestinationDatumTransform( -1 )
 {
   setFinder();
   mSourceCRS = source;
@@ -65,6 +69,8 @@ QgsCoordinateTransform::QgsCoordinateTransform( long theSourceSrsId, long theDes
     , mDestCRS( theDestSrsId, QgsCoordinateReferenceSystem::InternalCrsId )
     , mSourceProjection( 0 )
     , mDestinationProjection( 0 )
+    , mSourceDatumTransform( -1 )
+    , mDestinationDatumTransform( -1 )
 {
   initialise();
 }
@@ -74,6 +80,8 @@ QgsCoordinateTransform::QgsCoordinateTransform( QString theSourceCRS, QString th
     , mInitialisedFlag( false )
     , mSourceProjection( 0 )
     , mDestinationProjection( 0 )
+    , mSourceDatumTransform( -1 )
+    , mDestinationDatumTransform( -1 )
 {
   setFinder();
   mSourceCRS.createFromWkt( theSourceCRS );
@@ -92,6 +100,8 @@ QgsCoordinateTransform::QgsCoordinateTransform( long theSourceSrid,
     , mInitialisedFlag( false )
     , mSourceProjection( 0 )
     , mDestinationProjection( 0 )
+    , mSourceDatumTransform( -1 )
+    , mDestinationDatumTransform( -1 )
 {
   setFinder();
 
@@ -137,7 +147,7 @@ void QgsCoordinateTransform::setDestCRSID( long theCRSID )
 
 // XXX This whole function is full of multiple return statements!!!
 // And probably shouldn't be a void
-void QgsCoordinateTransform::initialise( int srcDatumTransform, int destDatumTransform )
+void QgsCoordinateTransform::initialise()
 {
   // XXX Warning - multiple return paths in this block!!
   if ( !mSourceCRS.isValid() )
@@ -157,7 +167,7 @@ void QgsCoordinateTransform::initialise( int srcDatumTransform, int destDatumTra
     mDestCRS = QgsCRSCache::instance()->crsByAuthId( mSourceCRS.authid() );
   }
 
-  bool useDefaultDatumTransform = ( srcDatumTransform == - 1 && destDatumTransform == -1 );
+  bool useDefaultDatumTransform = ( mSourceDatumTransform == - 1 && mDestinationDatumTransform == -1 );
 
   // init the projections (destination and source)
   pj_free( mDestinationProjection );
@@ -166,9 +176,9 @@ void QgsCoordinateTransform::initialise( int srcDatumTransform, int destDatumTra
   {
     destProjString = stripDatumTransform( destProjString );
   }
-  if ( destDatumTransform != -1 )
+  if ( mDestinationDatumTransform != -1 )
   {
-    destProjString += ( " " +  datumTransformString( destDatumTransform ) );
+    destProjString += ( " " +  datumTransformString( mDestinationDatumTransform ) );
   }
   mDestinationProjection = pj_init_plus( destProjString.toUtf8() );
 
@@ -178,9 +188,9 @@ void QgsCoordinateTransform::initialise( int srcDatumTransform, int destDatumTra
   {
     sourceProjString = stripDatumTransform( sourceProjString );
   }
-  if ( srcDatumTransform != -1 )
+  if ( mSourceDatumTransform != -1 )
   {
-    sourceProjString += ( " " + datumTransformString( srcDatumTransform ) );
+    sourceProjString += ( " " + datumTransformString( mSourceDatumTransform ) );
   }
   mSourceProjection = pj_init_plus( sourceProjString.toUtf8() );
 
@@ -690,6 +700,9 @@ bool QgsCoordinateTransform::readXML( QDomNode & theNode )
   QDomNode myDestNode = theNode.namedItem( "destinationsrs" );
   mDestCRS.readXML( myDestNode );
 
+  mSourceDatumTransform = theNode.toElement().attribute( "sourceDatumTransform", "-1" ).toInt();
+  mDestinationDatumTransform = theNode.toElement().attribute( "destinationDatumTransform", "-1" ).toInt();
+
   initialise();
 
   return true;
@@ -699,6 +712,8 @@ bool QgsCoordinateTransform::writeXML( QDomNode & theNode, QDomDocument & theDoc
 {
   QDomElement myNodeElement = theNode.toElement();
   QDomElement myTransformElement = theDoc.createElement( "coordinatetransform" );
+  myTransformElement.setAttribute( "sourceDatumTransform", QString::number( mSourceDatumTransform ) );
+  myTransformElement.setAttribute( "destinationDatumTransform", QString::number( mDestinationDatumTransform ) );
 
   QDomElement mySourceElement = theDoc.createElement( "sourcesrs" );
   mSourceCRS.writeXML( mySourceElement, theDoc );
diff --git a/src/core/qgscoordinatetransform.h b/src/core/qgscoordinatetransform.h
index df3da1bdfdc0..3dae9be71368 100644
--- a/src/core/qgscoordinatetransform.h
+++ b/src/core/qgscoordinatetransform.h
@@ -214,9 +214,14 @@ class CORE_EXPORT QgsCoordinateTransform : public QObject
     /**Returns list of datum transformations for the given src and dest CRS*/
     static QList< QList< int > > datumTransformations( const QgsCoordinateReferenceSystem& srcCRS, const QgsCoordinateReferenceSystem& destCRS );
 
+    int sourceDatumTransform() const { return mSourceDatumTransform; }
+    void setSourceDatumTransform( int dt ) { mSourceDatumTransform = dt; }
+    int destinationDatumTransform() const { return mDestinationDatumTransform; }
+    void setDestinationDatumTransform( int dt ) { mDestinationDatumTransform = dt; }
+
   public slots:
     //!initialise is used to actually create the Transformer instance
-    void initialise( int srcDatumTransform = -1, int destDatumTransform = -1 );
+    void initialise();
 
     /*! Restores state from the given Dom node.
     * @param theNode The node from which state will be restored
@@ -268,6 +273,9 @@ class CORE_EXPORT QgsCoordinateTransform : public QObject
      */
     projPJ mDestinationProjection;
 
+    int mSourceDatumTransform;
+    int mDestinationDatumTransform;
+
     /*!
      * Finder for PROJ grid files.
      */
diff --git a/src/core/qgscrscache.cpp b/src/core/qgscrscache.cpp
index ef8f7331c646..48ed218e7488 100644
--- a/src/core/qgscrscache.cpp
+++ b/src/core/qgscrscache.cpp
@@ -39,22 +39,28 @@ QgsCoordinateTransformCache::~QgsCoordinateTransformCache()
   delete mInstance;
 }
 
-const QgsCoordinateTransform* QgsCoordinateTransformCache::transform( const QString& srcAuthId, const QString& destAuthId )
+const QgsCoordinateTransform* QgsCoordinateTransformCache::transform( const QString& srcAuthId, const QString& destAuthId, int srcDatumTransform, int destDatumTransform )
 {
-  QHash< QPair< QString, QString >, QgsCoordinateTransform* >::const_iterator ctIt =
-    mTransforms.find( qMakePair( srcAuthId, destAuthId ) );
-  if ( ctIt == mTransforms.constEnd() )
-  {
-    const QgsCoordinateReferenceSystem& srcCrs = QgsCRSCache::instance()->crsByAuthId( srcAuthId );
-    const QgsCoordinateReferenceSystem& destCrs = QgsCRSCache::instance()->crsByAuthId( destAuthId );
-    QgsCoordinateTransform* ct = new QgsCoordinateTransform( srcCrs, destCrs );
-    mTransforms.insert( qMakePair( srcAuthId, destAuthId ), ct );
-    return ct;
-  }
-  else
+  QList< QgsCoordinateTransform* > values =
+    mTransforms.values( qMakePair( srcAuthId, destAuthId ) );
+
+  QList< QgsCoordinateTransform* >::const_iterator valIt = values.constBegin();
+  for ( ; valIt != values.constEnd(); ++valIt )
   {
-    return ctIt.value();
+    if ( *valIt && ( *valIt )->sourceDatumTransform() == srcDatumTransform && ( *valIt )->destinationDatumTransform() == destDatumTransform )
+    {
+      return *valIt;
+    }
   }
+
+  //not found, insert new value
+  const QgsCoordinateReferenceSystem& srcCrs = QgsCRSCache::instance()->crsByAuthId( srcAuthId );
+  const QgsCoordinateReferenceSystem& destCrs = QgsCRSCache::instance()->crsByAuthId( destAuthId );
+  QgsCoordinateTransform* ct = new QgsCoordinateTransform( srcCrs, destCrs );
+  ct->setSourceDatumTransform( srcDatumTransform );
+  ct->setDestinationDatumTransform( destDatumTransform );
+  mTransforms.insertMulti( qMakePair( srcAuthId, destAuthId ), ct );
+  return ct;
 }
 
 void QgsCoordinateTransformCache::invalidateCrs( const QString& crsAuthId )
diff --git a/src/core/qgscrscache.h b/src/core/qgscrscache.h
index 81da0462a843..b7a10098b353 100644
--- a/src/core/qgscrscache.h
+++ b/src/core/qgscrscache.h
@@ -33,13 +33,13 @@ class CORE_EXPORT QgsCoordinateTransformCache
     /**Returns coordinate transformation. Cache keeps ownership
         @param srcAuthId auth id string of source crs
         @param destAuthId auth id string of dest crs*/
-    const QgsCoordinateTransform* transform( const QString& srcAuthId, const QString& destAuthId );
+    const QgsCoordinateTransform* transform( const QString& srcAuthId, const QString& destAuthId, int srcDatumTransform = -1, int destDatumTransform = -1 );
     /**Removes transformations where a changed crs is involved from the cache*/
     void invalidateCrs( const QString& crsAuthId );
 
   private:
     static QgsCoordinateTransformCache* mInstance;
-    QHash< QPair< QString, QString >, QgsCoordinateTransform* > mTransforms;
+    QMultiHash< QPair< QString, QString >, QgsCoordinateTransform* > mTransforms; //same auth_id pairs might have different datum transformations
 };
 
 class CORE_EXPORT QgsCRSCache