diff --git a/README b/README
index c8f2504..da7314d 100644
--- a/README
+++ b/README
@@ -39,6 +39,9 @@ If you want to use the OPDS feed don't forget to specify feed.php at the end of
 On any Debian base Linux you can use :
  aptitude install php5-gd php5-sqlite php5-json
 
+On Centos you may have to add :
+ yum install php-xml
+
 = Install =
 
 1.  Extract the zip file to a folder in web space (visible to the web server).