diff --git a/Gemfile.lock b/Gemfile.lock
index c05d90a..565563a 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    powertrack (1.0.1)
+    powertrack (1.0.2)
       em-http-request (~> 1.1)
       eventmachine (~> 1.0)
       exponential-backoff (~> 0.0.2)
diff --git a/lib/powertrack/rules/rule.rb b/lib/powertrack/rules/rule.rb
index 8304dd3..48e8386 100644
--- a/lib/powertrack/rules/rule.rb
+++ b/lib/powertrack/rules/rule.rb
@@ -62,7 +62,7 @@ def valid?
     end
 
     # Dumps the rule in a valid JSON format.
-    def to_json(*options)
+    def to_json(options={})
       MultiJson.encode(to_hash, options)
     end