Draping an image over a dem...

Pardon our ignorance:
  Is there a grass command to drape an image over a dem when
  the dem is represented by several files, because it is large?
  We have TM data to drape over a dozen or so USGS quad dems,
  and we'd prefer not to have to generate the combined dem.
  Is this a problem for other folks?

  If you have any answers to our simple problem, please respond to

  STU_WISCUDDE@VAX1.ACS.JMU.EDU

  BIll Scudder
  Graduate Student
  James Madison University
  Harrisonburg, Virginia.

      GO DUKES!!