AutoCAD 2009 Essentials

Click the Alternate Units tab and you will see the following:

If you want two numbers to appear for each dimension, click on Display alternate units.
Specify the Alternate Unit format, its Precision, the Multiplier for all units' value, the Round distance, the Prefix, the Suffix, and the Zero suppression criteria.
Specify whether to show the alternate units After primary value or Below primary value.