diff -urN 1/src/tail.c 2/src/tail.c
--- 1/src/tail.c	2005-03-25 23:51:05.000000000 +0000
+++ 2/src/tail.c	2005-03-30 14:20:21.000000000 +0000
@@ -1375,7 +1375,7 @@
   const char *p = argv[1];
   const char *n_string;
   const char *n_string_end;
-  bool obsolete_usage;
+  bool obsolete_usage, obsolete_usage_posixly_correct;
   int default_count = DEFAULT_N_LINES;
   bool t_from_start;
   bool t_count_lines = true;
@@ -1387,7 +1387,8 @@
   if (argc < 2)
     return false;
 
-  obsolete_usage = (posix2_version () < 200112) || !getenv ("POSIXLY_CORRECT");
+  obsolete_usage = (posix2_version () < 200112);
+  obsolete_usage_posixly_correct = !getenv ("POSIXLY_CORRECT");
 
   switch (*p++)
     {
@@ -1395,10 +1396,6 @@
       return false;
 
     case '+':
-      /* Leading "+" is a file name in the non-obsolete form.  */
-      if (!obsolete_usage)
-	return false;
-
       t_from_start = true;
       break;
 
@@ -1446,10 +1443,11 @@
 
       if (!obsolete_usage)
 	{
-	  error (0, 0, _("`%s' option is obsolete; use `%s-%c %"PRIuMAX"'"),
+	  error (0, 0, _("`%s' option is obsolete; use `%s-%c %"PRIuMAX"' since this will be removed in the future"),
 		 argv[1], t_forever ? "-f " : "", t_count_lines ? 'n' : 'c',
 		 *n_units);
-	  usage (EXIT_FAILURE);
+	  if (!obsolete_usage_posixly_correct)
+		  usage (EXIT_FAILURE);
 	}
     }