I'm not sure why you want to cast, or even spec into ice barrier for a multiboxed mage, but you can see my mage's frost spec in her armory from the drop down menu by my name at the left of this post, and i think my frost macros in the thread linked in my signature are still up to date since i never really changed them. Just remember to get the main dps macro and the pop cooldowns one.

And if you get the "addon" from http://wow.curse.com/downloads/wow-a...ject-8021.aspx
You won't need the SFX lines in your macros anymore.