--- /dev/null
+--- bkchem/paper.py.orig 2005-08-04 07:18:12.000000000 +0200
++++ bkchem/paper.py 2005-08-04 07:20:09.000000000 +0200
+@@ -1558,8 +1558,11 @@
+
+
+ def any_color_to_rgb_string( self, color):
+- r, g, b = map( lambda x: (x < 256 and x) or (x >= 256 and x//256), self.winfo_rgb( color))
+- return "#%02x%02x%02x" % (r,g,b)
++ if not color:
++ return "none"
++ else:
++ r, g, b = map( lambda x: (x < 256 and x) or (x >= 256 and x//256), self.winfo_rgb( color))
++ return "#%02x%02x%02x" % (r,g,b)
+
+
+