The new Home Affordable Refinance Program has increase the borrowing limits to 125% of current house values. Homeowners now have an option to borrow more or face foreclosure.
The 125% loan-to-value (LTV) encourages more borrowing from house owners who maybe already be underwater as compared to the original refi programs offered by Fannie Mae or Freddie Mac with a 105% LTV.
http://www.housingwire.com/2009/07/01/hud-expands-home-affordable-refis-to-125-ltv/