AutoCAD 2010 :: User Supplied Text In Dimensions From Properties Palette

The help file for user-supllied text added to dimensions says, "To add user text above and below the dimension line, use the separator symbol X. Text that precedes this symbol is aligned with and above the dimension line. Text that follows the X symbol is aligned with and below the dimension line."

How do I get the same effect from the dimension Properties Palette later?  Would I have to re-create a dimension to do this in another session?  I need text below the dimension on a new line, and have not been able to do it using the Suffix field in the Properties.  Adding text there only appends it on the same line. (Or, am I missing a trick here?).