It always grabs my attention when I see a company’s stock rise 25%. And that’s what’s happening in after market trading at Digital Generation — a firm that distributes ads, syndicated programs, and video news releases to TV stations and other media companies. Its shares rocketed from a $9.61 closing price today after it announced that it has hired Goldman Sachs to help with a “strategic review,” which is usually code for seeking a buyer.  Last month it rejected a more than $20 a share offer from an Internet-based rival, Extreme Reach, fearing that it wouldn’t pass muster with antitrust officials, Bloomberg reported. Digital Generation’s stock is down 68% over the last 12 months.