He may have a problem with impacted anal glands or he might have picked up a protozoan parasite such as coccidia or giardia or he might have both problems.
You can read about anal sac problems here
www.marvistavet.com/html/anal_sacs.html
Some dogs also 'scoot' when they have poop stuck on them so this could be from the diarrhea too.
A vet visit should help you clear this all up. Bring a fresh stool sample to be checked for parasites.
Hope this helps you!
Edited by NHolmes on August 22 2005 at 12:31 PM
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