need to dup strings, some may be frozen

lib/post_creator.rb

@@ -54,13 +54,13 @@ class PostCreator
     # If we don't do this we introduce a rather risky dependency
     @user = user
     @opts = opts || {}
-    pg_clean_up!(opts[:title])
-    pg_clean_up!(opts[:raw])
+    opts[:title] = pg_clean_up(opts[:title]) if opts[:title]
+    opts[:raw] = pg_clean_up(opts[:raw]) if opts[:raw]
     @spam = false
   end
 
-  def pg_clean_up!(str)
-    str.gsub!("\u0000", "") if str
+  def pg_clean_up(str)
+    str.gsub("\u0000", "")
   end
 
   # True if the post was considered spam