diff --git a/firewall/ipfw.py b/firewall/ipfw.py
index 79fe7c66..41fbc29b 100644
--- a/firewall/ipfw.py
+++ b/firewall/ipfw.py
@@ -39,7 +39,7 @@ class Ipfw(Firewall):
 	
 	crtRuleNbr = 0
 	
-	def getCrtRuleNbr():
+	def getCrtRuleNbr(self):
 		""" Gets the current rule number.
 		"""
 		return self.crtRuleNbr