g1smd - 12:01 am on May 20, 2011 (gmt 0)
Do make sure there are no spaces in any part of the query string or filepath parts of the URL.
A redirect to redirect all non-canonical URL versions could be as short as 2 or 4 lines of code.
The canonical tag goes on all copies of the page. It informs search engines what the real URL for the content should be.