After 2012, Sprint faces a steady stream of debt that comes due. Maturing bonds and their potential demand on cash total $1.77 billion in 2013, $1.35 billion in 2014, $2.14 billion in 2015, $2 billion in 2016, $1.3 billion in 2017, and more beyond that year.
They will be out of cash after paying debt in 2011 and 2012.....
What you are saying is that Sprint will not generate any revenue during the next 7 years even though they have some cash on hand to pay off some of that debt and also have the opportunity to refinance some of it as well.
Go crawl back under the rock from which you came from.