500 error on discount

-- HikaShop version -- : 2.3.4
-- Joomla version -- : 2.5.27

Hi,
i noticed an error when i try to open a discount to modify it.
I have:

500 - Si è verificato un errore.

DateTime::__construct(): Failed to parse time string (11 Ottobre 2014 09:40) at position 0 (1): Unexpected character

Torna al Pannello di controllo

I noticed that there is not the issue if the discount has not the start/end date

Could you help me please?
Thank you.
Regards

Hello,
This is probably a problem with the time zone setting of your Joomla configuration. Please make sure that it is configured properly.

Hi,
if you mean joomla global configuration > server > location setting > server time zone
I am in Italy and it is set to Rome.

Yes,
Now it works fine.
Thank you so much!
Regards