diff -up cups-1.3.6/backend/ipp.c~ cups-1.3.6/backend/ipp.c
--- cups-1.3.6/backend/ipp.c~	2008-03-05 15:40:11.000000000 +0000
+++ cups-1.3.6/backend/ipp.c	2008-03-12 12:55:20.000000000 +0000
@@ -544,12 +544,12 @@ main(int  argc,				/* I - Number of comm
     * Try loading authentication information from the environment.
     */
 
-    const char *ptr = getenv("AUTH_USERNAME");
+    const char *ptr = getenv("CUPSD_AUTH_USERNAME");
 
     if (ptr)
       cupsSetUser(ptr);
 
-    password = getenv("AUTH_PASSWORD");
+    password = getenv("CUPSD_AUTH_PASSWORD");
   }
 
  /*