diff -ur ojs-prev/lib/pkp/templates/form/textInput.tpl ojs/lib/pkp/templates/form/textInput.tpl
--- ojs-prev/lib/pkp/templates/form/textInput.tpl	2017-10-24 06:05:28.000000000 +0300
+++ ojs/lib/pkp/templates/form/textInput.tpl	2018-02-24 16:38:08.931273477 +0200
@@ -67,7 +67,7 @@
 	{if $FBV_class|strstr:"datepicker"} 
 		<input data-date-format="{$dateFormatShort|dateformatPHP2JQueryDatepicker}" type="hidden" 
 		name="{$FBV_name|escape}{if $FBV_multilingual}[{$formLocale|escape}]{/if}"
-		value="{if $FBV_multilingual}{$FBV_value[$formLocale]|escape}{else}{$FBV_value|escape}{/if}"
+		value="{if $FBV_multilingual}{$FBV_value[$formLocale]|escape}{else}{$FBV_value|date_format:"%Y-%m-%d"|escape}{/if}"
 		id="{$FBV_id|escape}{$uniqId}-altField" />
 	{/if}