Author: Dave Case
Date: 08/18/03

Programs: sander

Description: parallel minimizations where 3-point waters are to be shaken
             will actually not shake some of the waters.  This leads to
             results whose details depend upon the number of processors

Fix:  apply the following patch to amber7/src/sander/fastwt.f

------------------------------------------------------------------------------
*** fastwt.f	8 Jan 2002 06:46:10 -0000	7.12
--- fastwt.f	18 Aug 2003 17:09:55 -0000
***************
*** 152,159 ****
  c
  c       -- screen out residue if wrong resname
  c
-         IF (IPRES(I+1)-IPRES(I).NE.3) all3point = .false.
          IF (LBRES(I).NE.IWTNM) GO TO 10
  c
  c       -- screen out residue if an atom is fixed (belly) or
  c          if an atom name does not match or is duplicated
--- 152,159 ----
  c
  c       -- screen out residue if wrong resname
  c
          IF (LBRES(I).NE.IWTNM) GO TO 10
+         IF (IPRES(I+1)-IPRES(I).NE.3) all3point = .false.
  c
  c       -- screen out residue if an atom is fixed (belly) or
  c          if an atom name does not match or is duplicated
***************
*** 387,399 ****
              ISTART = IPRES(I)
              IEND = IPRES(I) + 2
  #ifdef MPI
!             if (istart.ge.iparpt(mytaskid)+1 .and.
       .            iend.le.iparpt(mytaskid+1)) then
! #endif
              CALL SETLEP (ISTART    ,IEND       ,X0        ,XH        ,
       *          NATOM     ,IORWAT    ,RBTARG     )
- #ifdef MPI
-             end if
  #endif
            END IF
     10   CONTINUE
--- 387,405 ----
              ISTART = IPRES(I)
              IEND = IPRES(I) + 2
  #ifdef MPI
!             if( mpi_orig) then
!                CALL SETLEP (ISTART    ,IEND       ,X0        ,XH,
!      *             NATOM     ,IORWAT    ,RBTARG     )
!             else
!                if (istart.ge.iparpt(mytaskid)+1 .and.
       .            iend.le.iparpt(mytaskid+1)) then
!                CALL SETLEP (ISTART    ,IEND       ,X0        ,XH,
!      *             NATOM     ,IORWAT    ,RBTARG     )
!                end if
!             end if
! #else
              CALL SETLEP (ISTART    ,IEND       ,X0        ,XH        ,
       *          NATOM     ,IORWAT    ,RBTARG     )
  #endif
            END IF
     10   CONTINUE
------------------------------------------------------------------------------

Temporary workarounds: none