diff --git a/source/blender/python/api2_2x/Draw.c b/source/blender/python/api2_2x/Draw.c
index 873e00b5a88..0c75ee22ab6 100644
--- a/source/blender/python/api2_2x/Draw.c
+++ b/source/blender/python/api2_2x/Draw.c
@@ -1045,6 +1045,11 @@ static PyObject *Method_String( PyObject * self, PyObject * args )
 			"expected a string, five ints, a string, an int and\n\
 	optionally another string as arguments" );
 
+	if (len > (UI_MAX_DRAW_STR - 1)) {
+		len = UI_MAX_DRAW_STR - 1;
+		newstr[len] = '\0';
+	}
+
 	real_len = strlen(newstr);
 	if (real_len > len) real_len = len;
 
@@ -1053,7 +1058,7 @@ static PyObject *Method_String( PyObject * self, PyObject * args )
 	but->slen = len;
 	but->val.asstr = MEM_mallocN( len + 1, "pybutton str" );
 
-	BLI_strncpy( but->val.asstr, newstr, len + 1 ); /* adds '\0' */
+	BLI_strncpy( but->val.asstr, newstr, len + 1); /* adds '\0' */
 	but->val.asstr[real_len] = '\0';
 
 	if (info_arg[0] == '\0') info_str = info_str0;
@@ -1244,7 +1249,7 @@ static PyObject *Method_Image( PyObject * self, PyObject * args )
 	float originX, originY;
 	float zoomX = 1.0, zoomY = 1.0;
 	int clipX = 0, clipY = 0, clipW = -1, clipH = -1;
-	GLfloat scissorBox[4];
+	/*GLfloat scissorBox[4];*/
 
 	/* parse the arguments passed-in from Python */
 	if( !PyArg_ParseTuple( args, "Off|ffiiii", &pyObjImage, 
@@ -1301,10 +1306,28 @@ static PyObject *Method_Image( PyObject * self, PyObject * args )
 	 * This particular technique is documented in the glRasterPos() man
 	 * page, although I haven't seen it used elsewhere in Blender.
 	 */
+
+	/* update (W): to fix a bug where images wouldn't get drawn if the bottom
+	 * left corner of the Scripts win were above a given height or to the right
+	 * of a given width, the code below is being commented out.  It should not
+	 * be needed anyway, because spaces in Blender are projected to lie inside
+	 * their areas, see src/drawscript.c for example.  Note: the
+	 * glaRasterPosSafe2i function in src/glutil.c does use the commented out
+	 * technique, but with 0,0 instead of scissorBox.  This function can be
+	 * a little optimized, based on glaDrawPixelsSafe in that same fine, but
+	 * we're too close to release 2.37 right now. */
+	/*
 	glGetFloatv( GL_SCISSOR_BOX, scissorBox );
 	glRasterPos2i( scissorBox[0], scissorBox[1] );
 	glBitmap( 0, 0, 0.0, 0.0, 
 		originX-scissorBox[0], originY-scissorBox[1], NULL );
+	*/
+
+	/* update (cont.): using these two lines instead:
+	 * (based on glaRasterPosSafe2i, but Ken Hughes deserves credit
+	 * for suggesting this exact fix in the bug tracker) */
+	glRasterPos2i(0, 0);
+	glBitmap( 0, 0, 0.0, 0.0, originX, originY, NULL );
 
 	/* set the zoom */
 	glPixelZoom( zoomX, zoomY );
diff --git a/source/blender/python/api2_2x/Mathutils.c b/source/blender/python/api2_2x/Mathutils.c
index 910b1587974..8c8a69f7a1d 100644
--- a/source/blender/python/api2_2x/Mathutils.c
+++ b/source/blender/python/api2_2x/Mathutils.c
@@ -25,7 +25,7 @@
  *
  * This is a new part of Blender.
  *
- * Contributor(s): Joseph Gilbert
+ * Contributor(s): Joseph Gilbert, Campbell Barton
  *
  * ***** END GPL/BL DUAL LICENSE BLOCK *****
  */
@@ -369,8 +369,19 @@ static PyObject *M_Mathutils_DotVecs( PyObject * self, PyObject * args )
 static PyObject *M_Mathutils_AngleBetweenVecs( PyObject * self,
 					       PyObject * args )
 {
+	// original vectors, makea copy of these
 	VectorObject *vec1;
 	VectorObject *vec2;
+	
+	/* copy of the 2 input vectors, these can be normalized
+	without input vectors being normalized. bugfix 
+	no need to use vector objects, just use floats
+	No Chance of 4D vectors getting in.
+	
+	Use doubles, since floats will return nan when input vecs are large.*/
+	double vec1copy[3];
+	double vec2copy[3];
+	
 	float norm;
 	double dot, angleRads;
 	int x;
@@ -386,30 +397,43 @@ static PyObject *M_Mathutils_AngleBetweenVecs( PyObject * self,
 	if( vec1->size > 3 || vec2->size > 3 )
 		return ( EXPP_ReturnPyObjError( PyExc_TypeError,
 						"only 2D,3D vectors are supported\n" ) );
-
-	//normalize vec1
+	
+	/* Check for 2 vectors being the same */
+	if (vec1->size == 3 &&
+		vec1->vec[0] == vec2->vec[0] &&
+		vec1->vec[1] == vec2->vec[1] &&
+		vec1->vec[2] == vec2->vec[2])
+			return PyFloat_FromDouble( dot ); /* 2 points are the same, return zero */
+	else if (vec1->size == 2 &&
+		vec1->vec[0] == vec2->vec[0] &&
+		vec1->vec[1] == vec2->vec[1])
+			return PyFloat_FromDouble( dot ); /* 2 points are the same, return zero */
+	
+	//normalize vec1copy
 	norm = 0.0f;
 	for( x = 0; x < vec1->size; x++ ) {
-		norm += vec1->vec[x] * vec1->vec[x];
+		vec1copy[x] = vec1->vec[x]; /* Assign new vector in the loop */
+		norm += vec1copy[x] * vec1copy[x];
 	}
 	norm = ( float ) sqrt( norm );
 	for( x = 0; x < vec1->size; x++ ) {
-		vec1->vec[x] /= norm;
+		vec1copy[x] /= norm;
 	}
 
-	//normalize vec2
+	//normalize vec2copy
 	norm = 0.0f;
 	for( x = 0; x < vec2->size; x++ ) {
-		norm += vec2->vec[x] * vec2->vec[x];
+		vec2copy[x] = vec2->vec[x]; /* Assign new vector in the loop */
+		norm += vec2copy[x] * vec2copy[x];
 	}
 	norm = ( float ) sqrt( norm );
 	for( x = 0; x < vec2->size; x++ ) {
-		vec2->vec[x] /= norm;
+		vec2copy[x] /= norm;
 	}
 
 	//dot product
 	for( x = 0; x < vec1->size; x++ ) {
-		dot += vec1->vec[x] * vec2->vec[x];
+		dot += vec1copy[x] * vec2copy[x];
 	}
 
 	//I believe saacos checks to see if the vectors are normalized
diff --git a/source/blender/python/api2_2x/vector.c b/source/blender/python/api2_2x/vector.c
index 9e65de3c46d..049ed793de6 100644
--- a/source/blender/python/api2_2x/vector.c
+++ b/source/blender/python/api2_2x/vector.c
@@ -23,7 +23,7 @@
  * All rights reserved.
  *
  * 
- * Contributor(s): Willian P. Germano & Joseph Gilbert
+ * Contributor(s): Willian P. Germano, Joseph Gilbert, Ken Hughes
  *
  * ***** END GPL/BL DUAL LICENSE BLOCK *****
  */
@@ -550,6 +550,10 @@ int Vector_coerce( PyObject ** v1, PyObject ** v2 )
 				printf( "vector/matrix numeric protocols unsupported...\n" );
 				Py_INCREF( *v1 );
 				return 0;	//operation will type check
+			} else if( *v2 == Py_None ) {
+				Py_INCREF(*v1);
+				Py_INCREF(Py_None);
+				return 0;
 			} else if( PyNumber_Check( *v2 ) ) {
 				if( PyInt_Check( *v2 ) ) {	//cast scalar to vector
 					tempI = PyMem_Malloc( 1 *
@@ -596,6 +600,7 @@ int Vector_coerce( PyObject ** v1, PyObject ** v2 )
 			//unknown type or numeric cast failure
 			printf( "attempting vector operation with unsupported type...\n" );
 			Py_INCREF( *v1 );
+			Py_INCREF( *v2 );
 			return 0;	//operation will type check
 		}
 	} else {