Is it ok for me to contact the HR person about a timetable for when the hiring manager will be calling?

I applied for a job and was contacted by an HR representative saiyng that my resume had been ped along to the hiring manager for review, and that she had looked it over and was going to be contacting me for a phone interview. During the cal with the HR rep she confirmed when I would be available to start, earliest would be be end of May 08. It has been a few weeks since that call,so would it be appropriate to follow-up and ask when she may be calling or what their timetable is? I don't want to sound desperate, but I will be relocating to the area where the job is wth my wife, and i"m anxious to have something lined up.Thanks.