Special character like ñ

I have a ispconfig3 and I have a client with two domains called ureña.es and urena.es.
I want to redirect ureña.es to urena.es.
I have created urena.es, but how can I create the domain called ureña.es at ispconfig?? The character ñ is not accepted at ISPconfig3

Can anybody help me, please???

 

Thanks

I was not to able to find it. Ihope my tags can help other people to find out the solution