no way.... as a gurl i love be given the guys number. it puts me in control and u are guarenteed that he really likes u and isnt going to never call. as guys sometimes do. i say go for it. slip it to her as friends. just go into ur old job for a visit. and be like we should hang out sometime. start small. u dont have to make it sound so official per say. im sure she will be flattered.