Dobson (DCEL) rose 3% Monday after posting strong second-quarter results.The Oklahoma City-based wireless shop released solid preliminary numbers reflecting a swing back to subscriber growth, a lower user defection rate and higher monthly customer bills. For the quarter ended last month, Dobson added 17,300 net new subscribers, compared with 2,500 added in the prior quarter and a loss of 1,100 users in the year-ago period. The higher net subscriber growth was due to a sharply reduced monthly cancellation rate. Dobson says defections, or churn, fell to 1.84% in the second quarter, down from 2.25% a year ago and 2% in the previous quarter. The company expects the average revenue per user to have jumped to $47.80 from $46.76 in the first quarter and $45.28 a year ago. Another strong measure of the company's improved performance came from its increased roaming proceeds. Dobson says it had about 675 million roaming minutes in the second quarter, compared with 517 million in the year-ago period, as more non-Dobson customers called from within the company's territory. The company says the roaming traffic yielded about 10.5 cents a minute, higher than Wall Street was expecting and well above the 9.7 cents in the first quarter. "The unexpectedly high roaming yields make this company more attractive" to other companies, says one investor who owns the stock. "This would be a great acquisition candidate for Cingular if this trend continues." Dobson shares rose 24 cents Monday to $7.94.