Is it possible that the object is too large for the 4kb cookie size limit and that's what is causing this error?<br><br>On Saturday, May 26, 2012 2:39:08 AM UTC-7, armanx wrote:<blockquote class="gmail_quote" style="margin: 0;margin-left: 0.8ex;border-left: 1px #ccc solid;padding-left: 1ex;">Hello everyone,<div><br></div><div>I'm using&nbsp;Rack::Session::Cookie to store an object (a Sequel model returned by a database call) in the session. However, I'm getting a "singleton can't be dumped" error when trying to do so. What is the reason for this error?</div><div><br></div><div>The interesting thing is, I only get the error when the Sequel object is first saved in the database then returned; the error is absent when the record already exists in the database and is returned via select (without saving), yet in both cases the objects/classes are identical.</div></blockquote>