Setting an option

I have:

<option name="MANAGED_MEMORY">
  <values>no,yes</values>
  <values-description>No,Yes</values-description>
</option>
	
<set var="USE_MANAGED_MEMORY" 
    cond="MANAGED_MEMORY=='yes'">-DEU_MANAGED_MEMORY</set>

Later:

<action...>
  <command>
    .. $(USE_MANAGED_MEMORY)

I was expecting that USE_MANAGED_MEMORY would be set to "-DEU_MANAGED_MEMORY" 
if I called, say, "wmake MANAGED_MEMORY=yes" but I don't even see how this 
would be in the Makefile and of course, it's not working.

What am I doing wrong for these types of values?

Jeremy



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