diff --git a/lib/77bit/packjt77.f90 b/lib/77bit/packjt77.f90
index b8a4ac424..9bd60f05d 100644
--- a/lib/77bit/packjt77.f90
+++ b/lib/77bit/packjt77.f90
@@ -824,7 +824,9 @@ subroutine split77(msg,nwords,nw,w)
   iz=j                                          !Message length
   nwords=k                                      !Number of words in msg
   if(nwords.le.0) go to 900
-  nw(k)=len(trim(w(k)))
+  do i=1,nwords
+     nw(i)=len(trim(w(i)))
+  enddo
   msg(iz+1:)='                                     '
   if(nwords.lt.3) go to 900
   call chkcall(w(3),bcall_1,ok1)
@@ -833,7 +835,7 @@ subroutine split77(msg,nwords,nw,w)
      w(2:12)=w(3:13)                    !Move all remaining words down by one
      nwords=nwords-1
   endif
-  
+
 900 return
 end subroutine split77