Using alphaGen lightingSpecular on a door shader

[DarthStevenus]

Like the title says, I'm trying to make the doors in my map have a nice specular shader. The shader works fine on normal brushes, but when I put it on an actual door entity, it behaves strangely. On my laptop, the spec map doesn't seem to show at all. On my desktop, I will stand a certain distance away from the door and not see the spec map, then when I take a few steps closer it will quickly pop in. Is there some key I have to set on the door entities?