diff --git a/includes/installer/Installer.php b/includes/installer/Installer.php
index 8cdde63..c53a3aa 100644
--- a/includes/installer/Installer.php
+++ b/includes/installer/Installer.php
@@ -791,6 +791,9 @@ abstract class Installer {
 		$caches = array();
 		foreach ( $this->objectCaches as $name => $function ) {
 			if ( function_exists( $function ) ) {
+				if ( $name == 'xcache' && !wfIniGetBool( 'xcache.var_size' ) ) {
+					continue;
+				}
 				$caches[$name] = true;
 			}
 		}
diff --git a/includes/objectcache/ObjectCache.php b/includes/objectcache/ObjectCache.php
index 25d4d47..99e3895 100644
--- a/includes/objectcache/ObjectCache.php
+++ b/includes/objectcache/ObjectCache.php
@@ -93,7 +93,7 @@ class ObjectCache {
 			$id = 'eaccelerator';
 		} elseif ( function_exists( 'apc_fetch') ) {
 			$id = 'apc';
-		} elseif( function_exists( 'xcache_get' ) ) {
+		} elseif( function_exists( 'xcache_get' ) && wfIniGetBool( 'xcache.var_size' ) ) {
 			$id = 'xcache';
 		} elseif( function_exists( 'wincache_ucache_get' ) ) {
 			$id = 'wincache';