diff --git a/reference/filesystem/reference.xml b/reference/filesystem/reference.xml
index 3589bda764..94e9c45517 100644
--- a/reference/filesystem/reference.xml
+++ b/reference/filesystem/reference.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.8 $ -->
+<!-- $Revision: 1.9 $ -->
  <reference id="ref.filesystem">
   <title>Filesystem functions</title>
   <titleabbrev>Filesystem</titleabbrev>
@@ -13,7 +13,12 @@
 
    <section id="filesystem.requirements">
     &reftitle.required;
-    &no.requirement;
+	<para>
+	 No external libraries are needed to build this extension, but if you want
+	 PHP to support LFS (large files) on Linux, then you need to have a recent
+	 glibc and you need compile PHP with the following compiler flags:
+	 <literal>-D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64</literal>.
+	</para>
    </section>
    
    <section id="filesystem.installation">