diff --git a/wp-includes/vars.php b/wp-includes/vars.php
index e8c97cf3d..2573b27eb 100644
--- a/wp-includes/vars.php
+++ b/wp-includes/vars.php
@@ -14,20 +14,18 @@
 
 // Simple browser detection
 $is_lynx = 0; $is_gecko = 0; $is_winIE = 0; $is_macIE = 0; $is_opera = 0; $is_NS4 = 0;
-if (!isset($HTTP_USER_AGENT)) {
-	$HTTP_USER_AGENT = $_SERVER['HTTP_USER_AGENT'];
-}
-if (preg_match('/Lynx/', $HTTP_USER_AGENT)) {
+
+if (preg_match('/Lynx/', $_SERVER['HTTP_USER_AGENT'])) {
 	$is_lynx = 1;
-} elseif (preg_match('/Gecko/', $HTTP_USER_AGENT)) {
+} elseif (preg_match('/Gecko/', $_SERVER['HTTP_USER_AGENT'])) {
 	$is_gecko = 1;
-} elseif ((preg_match('/MSIE/', $HTTP_USER_AGENT)) && (preg_match('/Win/', $HTTP_USER_AGENT))) {
+} elseif ((preg_match('/MSIE/', $_SERVER['HTTP_USER_AGENT'])) && (preg_match('/Win/', $_SERVER['HTTP_USER_AGENT']))) {
 	$is_winIE = 1;
-} elseif ((preg_match('/MSIE/', $HTTP_USER_AGENT)) && (preg_match('/Mac/', $HTTP_USER_AGENT))) {
+} elseif ((preg_match('/MSIE/', $_SERVER['HTTP_USER_AGENT'])) && (preg_match('/Mac/', $_SERVER['HTTP_USER_AGENT']))) {
 	$is_macIE = 1;
-} elseif (preg_match('/Opera/', $HTTP_USER_AGENT)) {
+} elseif (preg_match('/Opera/', $_SERVER['HTTP_USER_AGENT'])) {
 	$is_opera = 1;
-} elseif ((preg_match('/Nav/', $HTTP_USER_AGENT) ) || (preg_match('/Mozilla\/4\./', $HTTP_USER_AGENT))) {
+} elseif ((preg_match('/Nav/', $_SERVER['HTTP_USER_AGENT']) ) || (preg_match('/Mozilla\/4\./', $_SERVER['HTTP_USER_AGENT']))) {
 	$is_NS4 = 1;
 }
 $is_IE    = (($is_macIE) || ($is_winIE));
diff --git a/wp-settings.php b/wp-settings.php
index e5a28773b..f01ccb7e3 100644
--- a/wp-settings.php
+++ b/wp-settings.php
@@ -18,7 +18,6 @@ function unregister_GLOBALS() {
 
 unregister_GLOBALS(); 
 
-$HTTP_USER_AGENT = getenv('HTTP_USER_AGENT');
 unset( $wp_filter, $cache_userdata, $cache_lastcommentmodified, $cache_lastpostdate, $cache_settings, $category_cache, $cache_categories );
 
 if ( ! isset($blog_id) )