diff -Naur matplotlib-0.90.1-old/lib/matplotlib/backends/backend_svg.py matplotlib-0.90.1-newsvg/lib/matplotlib/backends/backend_svg.py
--- matplotlib-0.90.1-old/lib/matplotlib/backends/backend_svg.py	2007-06-02 05:14:34.000000000 -0400
+++ matplotlib-0.90.1-newsvg/lib/matplotlib/backends/backend_svg.py	2007-07-09 20:08:27.000000000 -0400
@@ -206,11 +206,39 @@
         if len(x)==0: return
         if len(x)!=len(y):
             raise ValueError('x and y must be the same length')
-
+        
         y = self.height - y
-        details = ['d="M %f,%f' % (x[0], y[0])]
-        xys = zip(x[1:], y[1:])
-        details.extend(['L %f,%f' % tup for tup in xys])
+        
+        bound = 3*gc.get_linewidth() # *3 just in case...
+        maxX = self.width + bound
+        minX = 0 - bound
+        maxY = self.height + bound
+        minY = 0 - bound        
+           
+        seqData = zip(x[:-1], x[1:], y[:-1], y[1:])
+        drop = [ (x1 < minX and x2 < minX) or (x1 > maxX and x2 > maxX) or 
+                 (y1 < minY and y2 < minY) or (y1 > maxY and y2 > maxY) 
+                                           for x1,x2,y1,y2 in seqData]
+        
+        startpos = 0
+        try: startpos = drop.index(False)
+        except ValueError: return #all lines were culled
+        
+        try:
+            xys = zip(x, y)
+            details = ['d="']
+            while True:
+                noDrop = True
+                endpos = drop.index(True, startpos)            
+                details.append('M %f,%f' % xys[startpos])
+                details.extend(['L %f,%f' % tup for tup in xys[startpos+1:endpos]])
+                noDrop = False
+                startpos = drop.index(False, endpos)
+        except ValueError:
+            if noDrop:
+                details.append('M %f,%f' % xys[startpos])
+                details.extend(['L %f,%f' % tup for tup in xys[startpos+1:]])
+
         details.append('"')
         details = ' '.join(details)
         self._draw_svg_element('path', details, gc, None)
@@ -220,6 +248,18 @@
         self.draw_arc(gc, gc.get_rgb(), x, y, 1, 0, 0, 0, 0)
 
     def draw_polygon(self, gc, rgbFace, points):
+        bound = 3*gc.get_linewidth()
+        maxX = self.width + bound
+        minX = 0 - bound
+        maxY = self.height + bound
+        minY = 0 - bound    
+        
+        drop = [ (x < minX) or (x > maxX) or 
+                 (y < minY) or (y > maxY)     for x, y in points]
+        
+        if(all(drop)):
+            return
+    
         details = 'points = "%s"' % ' '.join(['%f,%f'%(x,self.height-y)
                                               for x, y in points])
         self._draw_svg_element('polygon', details, gc, rgbFace)