ExchMbx is a command-line utility that lets you create user mailboxes, mail enable an AD object, move mailboxes and delete mailboxes among other tasks that can be done using the GUI.
Ex1:
ExchMbx -b cn=joe,dc=joe,dc=net -cr srv1:sg1:db2
Create mailbox for joe in Server srv1, storage group sg1, database db2.
Ex2:
ExchMbx -b cn=joe,dc=joe,dc=net -move srv1:sg1:db2
Ditto ex1 but move.
Ex3:
ExchMbx -b cn=joe,cn=users,dc=joe,dc=net -clear
Clear Exchange attrs for joe, will delete mailbox or
clean email addresses of mailenabled objects.
Ex4:
ExchMbx -b cn=gr1,cn=users,dc=joe,dc=net -me
Mail Enable group gr1
Ex5:
ExchMbx -b cn=con1,cn=users,dc=joe,dc=net -me joe@joeware.net
Mail Enable contact con1 with email address joe@joeware.net
ExchMbx can be obtained from joeware.net along with many other useful tools.
[examples sourced from the ExchMbx Usage page]