Yes, I know Leafeon gets it in Gen IV, and who knows how many others in Gen V.
Gen V has been absolutely
brutal for Pokemon-specific moves, abilities, and type combinations, it's kind of sad.
Not sure, I'll get back on that in a minute.
In the meantime, here's some help for your Diamond playthrough. I don't know if you have the ability to export your save file to your computer, but if you figure out a way, you can use this guy's calculator to find the Feebas tiles for the current day.
http://www.youtube.com/watch?v=GvEywzxomT8&feature=relmfu