Shares of wireless carrier Sprint Nextel Corp. (NYSE: S) are plunging after the company reported a large first quarter loss this morning. The company posted stronger-than-expected adjusted earnings, but this was not enough to reassure investors who pushed the stock down more than 3%.

Sprint Nextel posted a quarterly loss of $505 million, or 18 cents per share, compared with a loss of $211 million, or 7 cents, in the same period a year ago. Its quarterly numbers were dragged down by losses of more than 1 million subscribers and severance charges. However, excluding one-time charges, the company would have earned 4 cents. Analysts had expected earnings on that basis of only 2 cents per share, according to Thomson Financial. Revenue tumbled 7.5% to $9.3 billion, well below expectations of $9.4 billion.

The company said that its total subscribers number dropped by 1.09 million to 52.8 million, including 1.07 million post-paid customers. This was actually a good news since the company anticipated a loss of 1.07 million post-paid customers.

Sprint still expects further challenging times but, on the other side of the coin, the company is "making progress in methodically attacking the sources of our performance issues." The wireless carrier had a difficult 2007, but has shown signs of recovery since the beginning of this year. In addition, Chief Executive Officer Dan Hesse believes Sprint's finances will stabilize toward the end of the year.

Eliza Popescu is a financial writer for the online investment advisory service Investor's Observer.