Exhibit 12.1

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES

(in thousands)

 

     For the Year Ended December 31,  
     2001     2002     2003     2004     2005  

Earnings (loss)—

          

Loss before income taxes

   $ (10,090 )   $ (34,017 )   $ (29,789 )   $ (93,271 )   $ (88,593 )

Add fixed charges:

          

Interest expense on indebtedness

     692       1,936       990       4,480       6,557  

Estimated interest on rental expense

     341       329       300       1,611       3,900  

Amortization of deferred closing costs related to convertible notes

     —         294       156       521       816  

Amortization of discount on convertible notes

     —         511       271       —         —    
                                        

Total adjusted loss

   $ (9,057 )   $ (30,947 )   $ (28,072 )   $ (86,659 )   $ (77,320 )
                                        

Fixed charges—

          

Interest expense on indebtedness

   $ 692     $ 1,936     $ 990     $ 4,480     $ 6,557  

Estimated interest on rental expense

     341       329       300       1,611       3,900  

Amortization of deferred closing costs related to convertible notes

     —         294       156       521       816  

Amortization of discount on convertible notes

     —         511       271       —         —    
                                        

Total fixed charges

   $ 1,033     $ 3,070     $ 1,717     $ 6,612     $ 11,273  

Coverage deficiency

   $ (10,090 )   $ (34,017 )   $ (29,789 )   $ (93,271 )   $ (88,593 )