The nation's capital is fast becoming a haven for fashion entrepreneurs, Holly E. Thomas reports. Designer Dana Ayanna Greaves says she has made every possible mistake since launching her business in 2004, and there are times she still wants to drop out. But she's gaining exposure in the national media and counts celebrities such as singer Erykah Badu among her customers. This year, she's starting a line that emphasizes sophistication over fun. "I'm trying to grow up with the brand," she says.