periodically_call_remote doesn´t work properly

Hi everyone: I have some problems using periodically_call_remote, here is my code:

<%=periodically_call_remote(:url => 'http://localhost:3000', :frequency => '0.5', :update => {:success=>'imagen'})%> <div id="imagen"> <%=image_tag("/guarrada/Debug/foto.jpg") %> </div>

My problem is that when I load the web page, it works properly for 3 or 4 refresh, but after that I have the result of the attachment image. Ayone can say me what I´m doing wrong??

THANKS!!!

Attachments: http://www.ruby-forum.com/attachment/4557/matar.bmp