I have the same problem SP2010
in IE8/IE9 do not work if value in colum is required
but works very well in FF 4.0 in every cases
I have found a solution
http://spcd.codeplex.com/discussions/206907
but I am just testing this.
What do you think about that?
In spcd.js script
simply turn
if(choices.substr(choices.indexOf("|"),3) == "|0|") choices = choices.substr(0, choices.indexOf("|")+2);
into
choices = choices.substr(0, choices.indexOf("|")+2);