diff --git a/lib/rdoc/ruby_lex.rb b/lib/rdoc/ruby_lex.rb
index 7488b80773..95faeb0c1d 100644
--- a/lib/rdoc/ruby_lex.rb
+++ b/lib/rdoc/ruby_lex.rb
@@ -396,7 +396,9 @@ def token
     "r" => "/",
     "w" => "]",
     "W" => "]",
-    "s" => ":"
+    "s" => ":",
+    "i" => "]",
+    "I" => "]"
   }
 
   PERCENT_PAREN = {