=== modified file 'share/extensions/dxf_outlines.py'
--- share/extensions/dxf_outlines.py	2015-09-01 12:15:52 +0000
+++ share/extensions/dxf_outlines.py	2015-10-07 17:13:33 +0000
@@ -207,28 +207,28 @@
                 return
             p = cubicsuperpath.parsePath(d)
         elif node.tag == inkex.addNS('rect','svg'):
-            x = float(node.get('x'))
-            y = float(node.get('y'))
+            x = float(node.get('x', 0))
+            y = float(node.get('y', 0))
             width = float(node.get('width'))
             height = float(node.get('height'))
             d = "m %s,%s %s,%s %s,%s %s,%s z" % (x, y, width, 0, 0, height, -width, 0)
             p = cubicsuperpath.parsePath(d)
         elif node.tag == inkex.addNS('line','svg'):
-            x1 = float(node.get('x1'))
-            x2 = float(node.get('x2'))
-            y1 = float(node.get('y1'))
-            y2 = float(node.get('y2'))
+            x1 = float(node.get('x1', 0))
+            x2 = float(node.get('x2', 0))
+            y1 = float(node.get('y1', 0))
+            y2 = float(node.get('y2', 0))
             d = "M %s,%s L %s,%s" % (x1, y1, x2, y2)
             p = cubicsuperpath.parsePath(d)
         elif node.tag == inkex.addNS('circle','svg'):
-            cx = float(node.get('cx'))
-            cy = float(node.get('cy'))
+            cx = float(node.get('cx', 0))
+            cy = float(node.get('cy', 0))
             r = float(node.get('r'))
             d = "m %s,%s a %s,%s 0 0 1 %s,%s %s,%s 0 0 1 %s,%s z" % (cx + r, cy, r, r, -2*r, 0, r, r, 2*r, 0)
             p = cubicsuperpath.parsePath(d)
         elif node.tag == inkex.addNS('ellipse','svg'):
-            cx = float(node.get('cx'))
-            cy = float(node.get('cy'))
+            cx = float(node.get('cx', 0))
+            cy = float(node.get('cy', 0))
             rx = float(node.get('rx'))
             ry = float(node.get('ry'))
             d = "m %s,%s a %s,%s 0 0 1 %s,%s %s,%s 0 0 1 %s,%s z" % (cx + rx, cy, rx, ry, -2*rx, 0, rx, ry, 2*rx, 0)