Problem at insert or update a specific Date

Problem at insert or update a specific Date

Dear Support,

If I try insert or update a date field the end show me the message error related toFormat of the field.
I set the format to the column to "dd/MM/yyyy" after enter the date with this format at the moment of save the end send a message error 

the value of the given date '31/12/2012 'is not compatible with the specified date format' dd MMM yyyy HH:mm:ss' 

Could you help me please?

Thanks.

Paulo Miguel.