This excerpt taken from the SMG 10-Q filed May 6, 2009.
CHANGE IN CONTROL. Normally, your DSUs will vest and be settled only under the circumstances described in Sections 2 and 3(a). However, if there is a Change in Control, your DSUs will become 100% vested on the date of the Change in Control and will be settled as described in the Plan. You should read the Plan carefully to ensure that you understand how this may happen.
This excerpt taken from the SMG 8-K filed Feb 2, 2005.
Change in Control. The occurrence of any of the following events: