Product discount gives error and calendar not working

[aravot]

In Joomla 1.5 r9297 and VM 1.1 r1029
Both Simple layout and Extend layout view

Product discount calendar not working instead of numeric numbers it shows letters (y-mm-dd)

When saving give following error.

Warning: mktime() expects parameter 4 to be long, string given in /home/example.com/administrator/components/com_virtuemart/classes/ps_product_discount.php on line 125

Warning: mktime() expects parameter 4 to be long, string given in /home/example.com/administrator/components/com_virtuemart/classes/ps_product_discount.php on line 134

In Joomla 1.0.13 and VM 1.1 r1029

When saving confirmation message is blank.