Xcache Object Cache update to account for versions of Xcache prior to 1.3

object-cache.php.diff

Index: object-cache.php
===================================================================
--- object-cache.php	(revision 548800)
+++ object-cache.php	(working copy)
@@ -92,8 +92,8 @@
 	public function __construct() {
 		global $table_prefix;
 
-		if ( !function_exists( 'xcache_get' ) ) {
-			wp_die( 'You do not have XCache installed, so you cannot use the XCache object cache backend. Please remove the <code>object-cache.php</code> file from your content directory.' );
+		if ( !function_exists( 'xcache_unset_by_prefix' ) ) {
+			wp_die( 'You do not have XCache 1.3+ installed, so you cannot use the XCache object cache backend. Please remove the <code>object-cache.php</code> file from your content directory.' );
 		}
 
 		$this->prefix = DB_HOST.'.'.DB_NAME.'.'.$table_prefix;