[amelia] imputation of ordinal variables

Dear all, I don't understand how amelia handles imputation of ordinal variables. We can read in Amelia II: A Program for Missing Data: "Imputations for variables set as ordinal are created by taking the continuously valued imputation and using an appropriately scaled version of this as the probability of success in a binomial distribution. The draw from this binomial distribution is then translated back into one of the ordinal categories." This is not explicit enough for me. I don't understand what does "appropriately scaled" mean and what's the link with binomial distribution. Can you give me more explanations ? Thank you for your cooperation. V.Audigier