diff -r c41acb1465ee -r e4c26ee9c998 graphics/LD_Objects.py
--- a/graphics/LD_Objects.py	Fri Jul 10 11:41:07 2009 +0200
+++ b/graphics/LD_Objects.py	Thu Jul 23 17:50:26 2009 +0200
@@ -669,9 +669,9 @@
         # Draw input and output connectors
         self.Input.Draw(dc)
         self.Output.Draw(dc)
-        if "reference" in self.Errors:
+        if self.Errors.has_key("reference"):
             HighlightErrorZone(dc, name_pos[0], name_pos[1], name_size[0], name_size[1])
-        if typetext != "" and ("negated" in self.Errors or "rising" in self.Errors or "falling" in self.Errors):
+        if typetext != "" and (self.Errors.has_key("negated") or self.Errors.has_key("rising") or self.Errors.has_key("falling")):
             HighlightErrorZone(dc, type_pos[0], type_pos[1], type_size[0], type_size[1])
         
 
@@ -967,9 +967,9 @@
         # Draw input and output connectors
         self.Input.Draw(dc)
         self.Output.Draw(dc)
-        if "reference" in self.Errors:
+        if self.Errors.has_key("reference"):
             HighlightErrorZone(dc, name_pos[0], name_pos[1], name_size[0], name_size[1])
-        if typetext != "" and ("negated" in self.Errors or "rising" in self.Errors or "falling" in self.Errors):
+        if typetext != "" and (self.Errors.has_key("negated") or self.Errors.has_key("rising") or self.Errors.has_key("falling")):
             HighlightErrorZone(dc, type_pos[0], type_pos[1], type_size[0], type_size[1])