Howto set specific paypal locale / language?

-- HikaShop version -- : 2.3.4
-- Joomla version -- : 3.36
-- PHP version -- : 5.5.18
-- Browser(s) name and version -- : any

Hello,

I need the paypal payment page to be only german, regardless which country the user comes from or whatever browser setting he/she has.

I have tried the following, without success.

1. Setting the paypal url to: www.paypal.de/cgi-bin/webscr
Result: The redirect would not end in a payment form, but just in a merchant login form.

2. Setting the paypal url to: www.paypal.com/de/cgi-bin/webscr
Result: PayPal still displays in English, if a shipping country other than Germany (and Austria) is chosen

3. Inserting a hidden field in the checkout form:
<input type='hidden' name="lc" value="de_DE" />
and even
<input type='hidden' name="lc" value="de" />
or
<input type='hidden' name="lc" value="DE" />

Result: PayPal still displays in English, if a shipping country other than Germany (and Austria) is chosen

4. Also inserted an array key 'lc' => 'de' into the paypal vars array in paypal.php (plugins/hikashoppayment/paypal/) around line 59
Result: PayPal still displays in English, if a shipping country other than Germany (and Austria) is chosen

Any ideas on how to get this solved?

Thanks

Thanks I'll take a look at the paypal account again. It's not mine, so I'll know in a few days.