diff --git a/checkin_notes b/checkin_notes
index 8d6c8cab34..d3cffed76f 100755
--- a/checkin_notes
+++ b/checkin_notes
@@ -11185,6 +11185,7 @@ David  30 Aug 2005
     - include pubDate in RSS feed
     - change getallheaders() to apache_request_headers()
         (the former apparently not defined in PHP5)
+    - if apache_request_headers() is not defined, disable caching
 
     html/
         inc/
diff --git a/html/inc/cache.inc b/html/inc/cache.inc
index 5befe7ef17..70c3524b39 100644
--- a/html/inc/cache.inc
+++ b/html/inc/cache.inc
@@ -2,6 +2,12 @@
 
 require_once("../project/cache_parameters.inc");
 
+#ifdef apache_request_headers
+    $no_cache = false;
+#else
+    $no_cache = true;
+#endif
+
 // mechanism for caching commonly-accessed pages
 
 function make_cache_dirs() {
@@ -139,6 +145,8 @@ function get_cached_data($max_age,$params=""){
 }
 
 function start_cache($max_age, $params=""){
+    if ($no_cache) return;
+
     $path = get_path($params);
 
     cache_check_diskspace(); //Check free disk space once in a while
@@ -179,6 +187,8 @@ function start_cache($max_age, $params=""){
 // write output buffer both to client and to cache
 //
 function end_cache($max_age,$params=""){
+    if ($no_cache) return;
+
     // for the benefit of hackers
     if (strstr($params, "..")) {
         return;