diff -urN procps-3.1.15/ps/parser.c procps-3.1.15.new/ps/parser.c
--- procps-3.1.15/ps/parser.c	2003-12-23 17:58:06.000000000 -0600
+++ procps-3.1.15.new/ps/parser.c	2003-12-24 13:45:08.000000000 -0600
@@ -315,12 +315,10 @@
       exclusive("-V");
       display_version();
       exit(0);
-#if 0
-    case 'Z':     /* full Mandatory Access Control level info */
-      trace("-Z shows full MAC info\n");
-      return "Don't understand MAC on Linux.";
+    case 'Z':
+      trace("-Z shows SELinux contexts\n");
+      format_flags |= FF_Fc;
       break;
-#endif
     case 'a':
       trace("-a select all with a tty, but omit session leaders.\n");
       simple_select |= SS_U_a;