In most of my drupal 6 sites, I use pathauto, xmlsitemap and nodewords. I like having canonical tags for all pages, as an added layer of protection against having duplicate content.
My site's front page is set to "node/31". The problem I ran into this morning was that Google had indexed "node/31" as the front page. (It was in my XML sitemap, as well as the canonical tag.) So I installed globalredirect, and so now "node/31" redirects to the "/". I also removed the home page from the xmlsitemap. I assume that google will soon remove "node/31" from its index. All is good... except that the canonical tag still shows "node/31".
I'm sure there is an easy solution here, but for some reason I just can't think what it is. The easiest solution would seemingly be to create a path alias for "node/31" to "/", but that's not possible. I also tried to set the canonical tag for the front page via admin/content/nodewords/meta-tags/frontpage but it seems to have no effect.