This is the print screen and the two http post :
FTS_ComponentId=&FTS_Unid=&FTS_Start=20130514T040000%2C00Z&FTS_End=20130520T040000%2C00Z&FTS_Duration=6&FTS_All_Invitee=CN%3DFran%C3%A7ois%20L%C3%A9veill%C3%A9%2FO%3D---
s_ItemList=AppointmentType%3BCategories%3BChair%3BLocation%3BRoom%3BTaskType%3BTopic%3BSubject&s_ApptUnid=&s_StartDate=20130514T040000%2C00Z&s_EndDate=20130520T040000%2C00Z&s_UserList=CN%3DFran%C3%A7ois%20L%C3%A9veill%C3%A9%2FO%3D---
What can I understand is the browser doesn't questioned the invitees !!! Biz.