Send-As with Exchange 2007
Sometimes you want to “send as” instead of send-on-behalf.
If you want to send an e-mail with your account but don’t want to see the recipient that it has been send with another account, you can use the send-as function in Exchange 2007.
The only problem is that this option cannot be configured via The Exchange Management Console.
Open the Exchange Management Shell and execute following commands:
[PS] C:Documents and SettingsAdministrator>Add-ADPermission <SendAsAccount> -ExtendedRights Send-As -user <YourAccount>
[PS] C:Documents and SettingsAdministrator>Add-MailboxPermission <SendAsAccount> -AccessRights FullAccess -user <YourAccount>