The IRS is implementing an inbound efax system. Because of this, the CAF Unit (Centralized Authorization Files) fax numbers have changed. For non-tax professionals, the CAF Unit handles IRS Power of Attorney and Tax Information Authorization forms.
For tax professionals, you can see the changes here. The old fax numbers will still work through the rest of 2012. The new numbers (which are toll-free numbers) are:
Ogden CAF Unit Fax Number: (855) 214-7522
Memphis CAF Unit Fax Number: (855) 214-7519