That is too funny. Well, I guess it probably isn't funny to you though since he is making a mess. How about a large bath mat? I have see some no-spill type of bowls that he wouldn't be able to get into in different pet catalogs. Here is an example. It is listed as a travel bowl but would probably solve your problem:

http://www.drivingcomfort.com/index..../5703/sc/54062