Collection titles containing a Dash surrounded by spaces, fail

[had24-gh]

I've written a function to dynamically select the six most recently published Collections and display them within a top navigation drop down list for selection. The menu displays a maximum of six items with the most recent positioned first in the top left and as additional Collections are published the sixth item in the bottom right menu position drops off the (3x2) menu and the new collection item assumes the upper top left position (all available Collection items are available on a Collections listing page). It works pretty well. The one issue I'm experiencing is that if a Collection title contains a dash (- en dash) surrounded by spaces the page fails to load when selected from the ddl with a template can't be found exception. The same item, however, is available from the Collections listing page by selecting its title and if the spaces surrounding the dash are removed, it also works from the drop down menu. I've tried using the url_encode filter on the portion of the url obtained from the collection title but to no effect. In the meantime, I've asked my users to not include this character combo in their Collection titles. Just wondering if anyone happens to have come across this and solved it?