Add a text box to the form. Name the field appropriately (like Ernesto suggested - CCEmail is a good name). Then in Data Connections, select the Email data connection. Click Modify. Walk through the data connection, when you get to the window where you can enter either a value for CC or click the fx button, click the fx button. In the formula editor select the button to insert a field or group. Select the new field you just added, and finish walking through the data connection.