Applied patch for preview caching (closes #1484186)

CHANGELOG

@@ -1,6 +1,11 @@
 CHANGELOG RoundCube Webmail
 ---------------------------
 
+2007/01/07 (thomasb)
+----------
+- Applied patch for preview caching (closes #1484186)
+- Added Thai localization files
+
 2006/12/29 (thomasb)
 ----------
 - Added error handling for attachment uploads

program/steps/mail/show.inc

@@ -23,8 +23,11 @@ require_once('Mail/mimeDecode.php');
 
 $PRINT_MODE = $_action=='print' ? TRUE : FALSE;
 
-// allow this request to be cached
-send_future_expire_header();
+// allow caching, unless remote images are present
+if ((bool)get_input_value('_safe', RCUBE_INPUT_GET))
+  send_nocacheing_headers();
+else
+  send_future_expire_header();
 
 // similar code as in program/steps/mail/get.inc
 if ($_GET['_uid'])