diff --git a/admin/company_preferences.php b/admin/company_preferences.php
index b23c92c7b..9407f15c5 100644
--- a/admin/company_preferences.php
+++ b/admin/company_preferences.php
@@ -113,7 +113,7 @@
 				'postal_address','phone', 'fax', 'email', 'coy_logo', 'domicile',
 				'use_dimension', 'curr_default', 'f_year', 'shortname_name_in_list',
 				'no_item_list' => 0, 'no_customer_list' => 0, 
-				'no_supplier_list' =>0, 'base_sales', 
+				'no_supplier_list' =>0, 'base_sales', 'ref_no_auto_increase' => 0,
 				'time_zone' => 0, 'company_logo_report' => 0, 'barcodes_on_stock' => 0, 'add_pct', 'round_to', 'login_tout', 
 				'auto_curr_reval', 'bcc_email', 'alternative_tax_include_on_docs', 'suppress_tax_rates',
 				'use_manufacturing', 'use_fixed_assets'))
@@ -161,6 +161,12 @@
 	$myrow["company_logo_report"] = get_company_pref("company_logo_report");
 }
 $_POST['company_logo_report']  = $myrow["company_logo_report"];
+if (!isset($myrow["ref_no_auto_increase"]))
+{
+	set_company_pref("ref_no_auto_increase", "setup.company", "tinyint", 1, '0');
+	$myrow["ref_no_auto_increase"] = get_company_pref("ref_no_auto_increase");
+}
+$_POST['ref_no_auto_increase']  = $myrow["ref_no_auto_increase"];
 if (!isset($myrow["barcodes_on_stock"]))
 {
 	set_company_pref("barcodes_on_stock", "setup.company", "tinyint", 1, '0');
@@ -208,6 +214,7 @@
 check_row(_("Time Zone on Reports"), 'time_zone', $_POST['time_zone']);
 check_row(_("Company Logo on Reports"), 'company_logo_report', $_POST['company_logo_report']);
 check_row(_("Use Barcodes on Stocks"), 'barcodes_on_stock', $_POST['barcodes_on_stock']);
+check_row(_("Auto Increase of Document References"), 'ref_no_auto_increase', $_POST['ref_no_auto_increase']);
 label_row(_("Database Scheme Version"), $_POST['version_id']);
 
 table_section(2);
diff --git a/sales/includes/cart_class.inc b/sales/includes/cart_class.inc
index 7d68e2a46..6aefabf72 100644
--- a/sales/includes/cart_class.inc
+++ b/sales/includes/cart_class.inc
@@ -285,12 +285,19 @@ class Cart
 	// Makes parent documents for direct delivery/invoice by recurent call.
 	// $policy - 0 or 1:  writeoff/return for IV, back order/cancel for DN
 	function write($policy=0) {
-
+		
+		global $SysPrefs, $Refs;
+		
 		begin_transaction(); // prevents partial database changes in case of direct delivery/invoice
 		if ($this->reference != 'auto' && $this->trans_no == 0 && !is_new_reference($this->reference, $this->trans_type))
 		{
-			commit_transaction();
-			return -1;
+			if (!empty($SysPrefs->prefs['ref_no_auto_increase']))
+				$this->reference = $Refs->get_next($this->trans_type, null, array('date' => Today()));
+			if (!is_new_reference($this->reference, $this->trans_type))	
+			{
+				commit_transaction();
+				return -1;
+			}	
 		}
 		if (count($this->src_docs) == 0 && ($this->trans_type == ST_SALESINVOICE || $this->trans_type == ST_CUSTDELIVERY) && !$this->is_prepaid()) {
 			// this is direct document - first add parent