by chance, is the periodically_call_remote function inside the element you are updating?
example;
view
<div id="update_me"> ... <%= periodically call remote :url => ..., :fequency => 60, :update => "update_me" -%> </div>
rjs
page.replace_html :partial => 'some_partial'
where _some_partial contains a call to periodically_call_remote