Yes there are a couple of ways to do this, you can use LDAP for aliasing and masquerading. Basically Aliasing is a way of rewriting the recipient address to a different value by using LDAP Attributes, and masquerading is the form of rewriting the sender address mainly used for outbound connections.
These are documented in the Userguides and also extra pointers on the support portal.
If however you don't have LDAP you can use the command aliasconfig which holds a static table of addresses to change from.
Hope this helps
