My user profile page renders user profiles using the following code
<SPSWC:ProfilePropertyValue PropertyName="DDI" dir="ltr" runat="server"/>
however in one environment the results are plain text
<div>DDI : 123 456 789</div>
and the other
<div>DDI : <a href='http://spportal/search/Pages/peopleresults.aspx?k="123%20456%20789"'>123 456 789</a></div>
While the search url brings back results in both environments, prooving that the profiles are set up and the information searchable, I cannot seem to find the SharePoint setting that changes this rendering behaviour.
Note: The users email address and manager property render correctly (as mailto and user profile links respectively) so it appears to be some search setting I am forgetting.