********> bugfix.13
Author:   Bill Ross
Date:     Jan 7, 1998

Programs: 	Carnal

Severity: 	Moderate

Description:	The BACKBONE option to the TORSION cmd fails to detect
		main-chain atoms.

Fix:		Make the following change to pointax.c:

-----------------------------------------------------------------------
*** OLD pointax.c
--- NEW pointax.c
***************
*** 398,404
  			nleap++;
  		AtomTree += 4;
  	}
! 	if (nmain == 0) {
  		printf("No main chain atoms.\n");
  		if (nleap)
  		    printf("(Old Leap prmtop's did not save chain info.)\n");

--- 398,404 -----
  			nleap++;
  		AtomTree += 4;
  	}
! 	if (maxarr == 0) {
  		printf("No main chain atoms.\n");
  		if (nleap)
  		    printf("(Old Leap prmtop's did not save chain info.)\n");
-----------------------------------------------------------------------