I've set up some Contacts in Exchange 2003 on my 2003SBS server specifying an external email address (eg firstname.lastname@example.org) and I've set a forward in Exchange General to the Contact, where in turn the external email address is specified. But although emails come in to the users' main AD accounts as normal, they don't forward to the external addresses.
I've looked at a few hits on this and done the obvious suggestions such as ticking all boxes in Exchange / Global Settings / Default/PropertiesAdvanced but to no avail. Dismounted & remounted the Store and restarted the Information Store Service. Still nothing. The external email addresses are accepting email ok when sent directly to them.