diff -r 8a9a34be09e0 -r d775bd70f571 src/Pure/General/position.ML
--- a/src/Pure/General/position.ML	Thu Jun 24 16:27:40 2010 +0100
+++ b/src/Pure/General/position.ML	Thu Jun 24 21:57:18 2010 +0200
@@ -67,8 +67,8 @@
 fun advance_count "\n" (i: int, j: int, k: int) =
       (if_valid i (i + 1), if_valid j 1, if_valid k (k + 1))
   | advance_count s (i, j, k) =
-      if Symbol.is_regular s andalso not (Symbol.is_utf8_trailer s)
-      then (i, if_valid j (j + 1), if_valid k (k + 1)) else (i, j, k);
+      if Symbol.is_regular s then (i, if_valid j (j + 1), if_valid k (k + 1))
+      else (i, j, k);
 
 fun invalid_count (i, j, k) =
   not (valid i orelse valid j orelse valid k);