Customer Language in Workflow Rules

Customer Language in Workflow Rules

Hi All,
I basicly have two main languages: english and italian.

I created a workflow rule that sends an email when an order is voided, but it doesn't let me filter the customer's language.
I want to send the english template if customer's language is english and so on.
Here is the screenshot of how appears the customer language menu on the workflow rules. What am I missing?