===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/less/cvt.c,v
retrieving revision 1.5
retrieving revision 1.6
diff -u -r1.5 -r1.6
--- src/usr.bin/less/cvt.c	2015/11/06 15:50:33	1.5
+++ src/usr.bin/less/cvt.c	2016/01/09 17:34:43	1.6
@@ -85,8 +85,8 @@
 					break;
 		} else {
 			/* Just copy the char to the destination buffer. */
-			if ((ops & CVT_TO_LC) && IS_UPPER(ch))
-				ch = TO_LOWER(ch);
+			if ((ops & CVT_TO_LC) && iswupper(ch))
+				ch = towlower(ch);
 			put_wchar(&dst, ch);
 			/* Record the original position of the char. */
 			if (chpos != NULL)