[gnu.emacs.gnus] what's wrong with this?

rusty@GARNET.BERKELEY.EDU (06/22/89)

Basically, I want the subjects sorted by date when I enter the
newsgroup.  So I stuck the following in my .emacs file:

(setq gnus-Subject-prepare-hook '(lambda () (gnus-Subject-sort-by-date nil)))

But when I try to go into a newsgroup I get some error message about
lisp level exceeded and am left in the top level newsgroup listing.

Can somebody please set me straight?