We trim the tail in a wedge starting at the tip and letting it get a tiny bit longer at the base near the tushy. If you do this and trim the tush they won't have so many 'issues' at potty time and clean up will be a breeze! We've always done this, even with full length coats, and it blends in perfectly. Here's the link to a thread I started about tails a while back and it has pictures of how ours are done.
http://www.yorkietalk.com/forums/sho...001#post456001