Strange Effect.Highlight behavior

I have the following code in my template:

<%= link_to_remote ("Delete", :update => "contents", :url => { :action => :delete, :id => }, :before => "'message_spinner')", :success => "Element.hide('message_spinner'); new Effect.Highlight('message1')") %>

When ‘Delete’ is clicked, the spinner is switched on then off as
expected, but the highlight effect doesn’t show. I’m expecting the
entire line to flash yellow - just like the ‘Click!’ link in this
example from

Interestingly, if I change “new Effect.Highlight(‘message1’)” to “new
Effect.Highlight(‘section2’)”, where “section2” is a Div element
elsewhere on the page, then “section2” does flash yellow!

Tested in Safari, Camino and Firefox.

Any thoughts?