[Plugin: WP-Invoice – Web Invoice and Billing] Russian Rouble ?

We’re going to add function to add any custom currency. Please, wait a little.

I second this request. I am from Argentina and we use “pesos”…

and we’re still waiting for this…

while you’re at it, you might as well make an option available to delete other currencies.

Thank you for pointing. You won’t be able to delete only currencies that you’ve already used just in few days.