Currency symbol gets lost on specific store view

Question

I got two store views in my shop.

1 english and 1 arabic(ar_SA)

Standard currency is SAR

On english store view the shop shows me SAR 100.00 for example. On arabic store view I just get the Number itself like 100.00.

Can someone tell me why the SAR is missing?

EDIT: Found out that in arabic store view the custom currency symbol is NOT used. Tested it by hard coding symbol in app/code/core/Mage/CurrencySymbol/Model/System/Currencysymbol.php (just for test)