Using '?' in routes


I am trying to get routes to work with the following:

map.connect ‘:controller/:action?:x,:y’

The above route does not work as it seems to get caught up on the ‘?’.
If I change the ‘?’ to any other separator character it works perfectly.

I am trying to get an image map to work
<%= link_to(image_tag(’/cage_layout.png’, :ismap => ‘true’), :action =>
‘show’) %>

Is there a way I can change how :ismap passes the variables (instead of

I am using rails 1.2.3 with ruby 1.8.5