--- a/bin/installto.sh	2016-03-30 15:46:11.686447589 +0200
+++ b/bin/installto.sh	2016-03-30 15:49:27.184064426 +0200
@@ -23,6 +23,9 @@
 
 require_once INSTALL_PATH . 'program/include/clisetup.php';
 
+// get arguments
+$opts = rcube_utils::get_opt(array('f' => 'force', 'y' => 'accept'));
+
 $target_dir = unslashify($_SERVER['argv'][1]);
 
 if (empty($target_dir) || !is_dir(realpath($target_dir)))
@@ -35,13 +38,15 @@
 
 $oldversion = $m[1];
 
-if (version_compare(version_parse($oldversion), version_parse(RCMAIL_VERSION), '>='))
+if (version_compare(version_parse($oldversion), version_parse(RCMAIL_VERSION), '>=') && !opts['force'])
   rcube::raise_error("Installation at target location is up-to-date!", false, true);
 
-echo "Upgrading from $oldversion. Do you want to continue? (y/N)\n";
-$input = trim(fgets(STDIN));
+if (!opts['accept']) {
+  echo "Upgrading from $oldversion. Do you want to continue? (y/N)\n";
+  $input = trim(fgets(STDIN));
+}
 
-if (strtolower($input) == 'y') {
+if ($opts['accept'] || strtolower($input) == 'y') {
   $err = false;
   echo "Copying files to target location...";
   $dirs = array('program','installer','bin','SQL','plugins','skins');
@@ -77,7 +82,11 @@
 
   if (!$err) {
     echo "Running update script at target...\n";
-    system("cd $target_dir && php bin/update.sh --version=$oldversion");
+    $command = "cd $target_dir && php bin/update.sh --version=$oldversion";
+    if ($opts['accept']) {
+      $command .= " --accept";
+    }
+    system($command);
     echo "All done.\n";
   }
 }