|Your telephonic co-worker is so far off the mark that she is in another area code. Although most employers do not want the employees using company's phones for personal calls unless there is a real emergency, that was obviously not the message your manager was sending to your associate. Rather, the point was that when employees come to work, it would be nice if they spent their time working.|
It is remarkable that your associate thinks that as long as she uses her own equipment, it is totally acceptable to chat all day. Under her assumption, although your company might not want employees sleeping at their desks, it would be permissible to zonk out all day if the employees bring a desk from home.
You and your associates can certainly tell your co-worker that you need her help and would appreciate her spending less time on her cell phone and more time on her work. If she gives you static, then you should mention the problem to your manager. However, it sounds like your manager is part of the problem itself. After all, if he were spending more time with the troops, your co-worker would automatically be doing less dialing.