Is it okay for dogs to eat cornbread?

I hated to ask this question in realtionship to the dog eating apples question, but it just occured that i need an answer to a cornbread issue. my border collie apparently cannot tolerate cornbread. i made this discovery in a horrible way. just left Cracker Barrel Restaurant and gave my border collie two cornbread muffins. bad mistake. left him in my car for approx. three hours. cool weather outside, windows down 2 inches from the top. i cannot describe the scene in the back seat of my Toyota. rubber gloves and a whole roll of paper towels did not touch this mess. after spraying a whole can of Lysol inside and the windows rolled down for a 40 mile ride home in the rain, the smell was no better. did the cornbread muffins have this effect on my dog?