There is no MAW voice pack, per se. You need to physically extract individual files from the MAW Sounds folder and transfer them to ETO. If you look in the MAW sounds file you will see files with extensions for Italian voice commands which, I believe, are "ita", "its" and "ity". For example "wingman_ita.gvp".
At least that's what I did. I learned this after encountering the same issue with the P-39 noted above. There should be another thread here on that topic as well which may provide additional information.
ADDENDUM: The post where I received this information (and which is clearer as to what to do) is entitled "No pilots voices with ICB in ETO". Read that one for more info.