Event view error

After adding a event when visit the event page I see drop down selectors for month and year on the top of the page. Selecting any month / year and click on "Filter" takes me to "Object not found" page.

The url is of the format : /events/2009-1

----------- error page ---------
Object not found!

The requested URL was not found on this server. The link on the referring page seems to be wrong or outdated. Please inform the author of that page about the error.

If you think this is a server error, please contact the webmaster.