Index: modules/aaa/mod_authnz_ldap.c
===================================================================
--- modules/aaa/mod_authnz_ldap.c	(revision 591167)
+++ modules/aaa/mod_authnz_ldap.c	(working copy)
@@ -29,6 +29,7 @@
 #include "apr_xlate.h"
 #define APR_WANT_STRFUNC
 #include "apr_want.h"
+#include "apr_lib.h"
 
 #if APR_HAVE_UNISTD_H
 /* for getpid() */
@@ -444,9 +445,7 @@
             char *str = apr_pstrcat(r->pool, "AUTHENTICATE_", sec->attributes[i], NULL);
             int j = 13;
             while (str[j]) {
-                if (str[j] >= 'a' && str[j] <= 'z') {
-                    str[j] = str[j] - ('a' - 'A');
-                }
+                str[j] = apr_toupper(str[j]);
                 j++;
             }
             apr_table_setn(e, str, vals[i]);