A thread on fredmiranda.com discusses this extensively, if it's length is any indication    

http://www.fredmiranda.com/forum/topic/264970

She's basically got it backward.

With the same lens, same aperture, focussed at the same point you reduce your DOF by going to (1.6 crop) DSLR.

Of course there are lots of permutations - as explained in the article above.

My friend is slowly switching to digital from film. She feels that Digital cameras with their crop factors have more depth of field for a given aperature and focal length than a film camera. Is she just rationalizing staying with film or is she correct? She shoots a Nikon F3 and d70 and now a d2x.

or, if you want to avoid this lengthy thread, take a look at the article "Digital SLRs and Depth of Field" from DOFMaster:

http://www.dofmaster.com/dof_dslr.html

Herman

Some of the confusion comes in comparing the DOF of the point & shoots which have very small sensors and are characterized as having "greater DOF" than DSLRs.  The point is that they also have very very small actual focal lengths on their lenses.  Eg the Canon PS A75 goes from 5.4 to 16.2mm  so the small sensor = shallower DOF effect is more than offset by a wide fl = deeper DOF.

You've probably seen the online calculator in the DOFMaster link above...