818476 You can configure either Exchange Server 2003 Standard Edition or Exchange Server 2003 Enterprise Edition as a front-end serverhttp://blog.flaphead.dns2go.com/archive/2005/05/16/1989.aspxExcellent they updated this ... I used to say that a when you had an Exchange 2003 Standard Edition FrontEnd you needed to have an Enterprise Edtion BackEnd which is wrong :-| Source http://support.microsoft.com/default.aspx?scid=kb;en-us;818476 ExchangeenCommunityServer 2.1 SP2 (Build: 61129.2)