multiple creditees

Has anyone been able to assign multiple creditees on a gift where one creditee is assigned the membership, then on the "matching/creditee" tab add another creditee with a $$ amount associated with the creditee?  I'm currently unable to do this - I am getting a message saying "additional creditee is not allowed" whenever I try to add a creditee (with and without a $$ amount associated).

Has anyone been able to get around this?  Or, if you have never had this problem, how do you have permissions for creditees set-up?

Thanks!