diff --git a/ext/json/lib/json/add/bigdecimal.rb b/ext/json/lib/json/add/bigdecimal.rb
index 539daeeaf5..c8b4f567cb 100644
--- a/ext/json/lib/json/add/bigdecimal.rb
+++ b/ext/json/lib/json/add/bigdecimal.rb
@@ -23,7 +23,7 @@ class BigDecimal
   end
 
   # return the JSON value
-  def to_json(*)
-    as_json.to_json
+  def to_json(*args)
+    as_json.to_json(*args)
   end
 end
diff --git a/ext/json/lib/json/add/complex.rb b/ext/json/lib/json/add/complex.rb
index 28ef734daf..4d977e7589 100644
--- a/ext/json/lib/json/add/complex.rb
+++ b/ext/json/lib/json/add/complex.rb
@@ -23,7 +23,7 @@ class Complex
   end
 
   # Stores class name (Complex) along with real value <tt>r</tt> and imaginary value <tt>i</tt> as JSON string
-  def to_json(*)
-    as_json.to_json
+  def to_json(*args)
+    as_json.to_json(*args)
   end
 end
diff --git a/ext/json/lib/json/add/rational.rb b/ext/json/lib/json/add/rational.rb
index 356940b225..6be4034581 100644
--- a/ext/json/lib/json/add/rational.rb
+++ b/ext/json/lib/json/add/rational.rb
@@ -22,7 +22,7 @@ class Rational
   end
 
   # Stores class name (Rational) along with numerator value <tt>n</tt> and denominator value <tt>d</tt> as JSON string
-  def to_json(*)
-    as_json.to_json
+  def to_json(*args)
+    as_json.to_json(*args)
   end
 end
diff --git a/ext/json/lib/json/add/regexp.rb b/ext/json/lib/json/add/regexp.rb
index a93866b05a..39d69fede7 100644
--- a/ext/json/lib/json/add/regexp.rb
+++ b/ext/json/lib/json/add/regexp.rb
@@ -24,7 +24,7 @@ class Regexp
 
   # Stores class name (Regexp) with options <tt>o</tt> and source <tt>s</tt>
   # (Regexp or String) as JSON string
-  def to_json(*)
-    as_json.to_json
+  def to_json(*args)
+    as_json.to_json(*args)
   end
 end