--- id.c	Wed Mar 31 07:28:44 1999
+++ id_uid.c	Sun Dec  2 20:51:45 2001
@@ -167,7 +167,11 @@
 
   if (argc - optind == 1)
     {
-      struct passwd *pwd = getpwnam (argv[optind]);
+      struct passwd *pwd;
+      if (isdigit(argv[optind][0]))
+        pwd = getpwuid ((uid_t) strtol (argv[optind], (char **) NULL, 10));
+      else
+        pwd = getpwnam (argv[optind]);
       if (pwd == NULL)
 	error (1, 0, _("%s: No such user"), argv[optind]);
       ruid = euid = pwd->pw_uid;