Index: src/undo.c
===================================================================
--- src/undo.c	(revision 57762)
+++ src/undo.c	(working copy)
@@ -3258,6 +3258,10 @@
     t = curbuf->b_u_line_colnr;
     if (curwin->w_cursor.lnum == curbuf->b_u_line_lnum)
 	curbuf->b_u_line_colnr = curwin->w_cursor.col;
+    if (Unix2003_compat) {
+        /* vi_05 test 276: "U" sets column to start of line */
+        t = 0;
+    } 
     curwin->w_cursor.col = t;
     curwin->w_cursor.lnum = curbuf->b_u_line_lnum;
     check_cursor_col();