Since Creo7 it works in a drawing. See Creo7 manual and video:
Place Multiple Normal Leader or Tangent Leader Annotations in Drawings
Use Add Leader for multiple normal or tangent leaders from a single annotation.
User Interface Location: Place a leader annotation normal or tangent in relation to your reference, right-click and select Add Leader. The Add Leader command is applicable to GTOLs (geometric tolerances) and notes. To add a normal or tangent leader for the non-modernized annotations (symbols and balloon notes), click Attachment and then click Add ref.
Release: Creo Parametric 188.8.131.52
It would be great if we could have this functionality in the model.