Ext-JS Quicktip Icon CSS问题

I've created a custom vtype to verify my emails, my TO field uses an exclamation.jpg icon, but I want my CC and BCC fields to use a warning icon (since its not req). I've been trying to wrap my head around navigating Ext-JS's API to determine what attributes I had access to (do I have access to attributes that the VType extends from?), and where I needed to specify this. I've created a custom vtype to verify my emails