Playfelt you said it! We seem to get blamed for it all! My daycare kids are 2 yr old angels! I'm not kidding, very rarely do I have to do any t/outs. The phrase is "where did he learn that?" Not here thanks. I've been thinking about this issue just this week, I know these kids get away with murder at home, but not at daycare!
I agree with everyone you need to use your "I mean business voice with him" All I have to do is look at my kids and they stop doing or fix their behaviour. But you MUST put him in a quiet place away from everyone even if he snivels, or starts to tear up, put him in the quiet spot asap. Any and all crying quiet spot asap, no talking just take him and talk when he stops crying. This should work after 2 or 3 days I would think, if not then there is another issue you may have to look for. Daycare training says to write down just for yourself when he starts to cry specifically, the time, whats going on around him, noisy, whatever and maybe you an come up with a solution your just over looking. Could it be separation anxiety from daddy?