set use-crt-filter-always

SET USE-CRT-FILTER-ALWAYS YES/no  -  whether to use CRT-FILTER always

With the YES setting, the screen pager defined by SET CRT-FILTER is used
  even for short messages.  This is usual for new users who have CRT-FILTER 
  set to /usr/ucb/more.mm -x.

If you change it to NO, the screen pager is used only when messages are
  too long for one screen.  This causes somewhat inconsistent results with
  CRT-FILTER as more.mm -x since the message [Press any key to continue]
  would appear only for messages longer than one screen.

If you have CRT-FILTER set to /usr/ucb/more -d, USE-CRT-FILTER-ALWAYS has
  no effect on screen, since more -d shows no prompt at the end of a long
  message.  The default setting then is NO.

For more help, type "help" and one of the following:
(at any prompt:)  save-init   set   show   set crt-filter   set user-level