AT&T Cingular Flip IV - Can I Change the Name of Speed Dial #1 from "Voicemail"?

My mom is 91 and will not be using Voicemail on her new AT&T Cingular Flip IV phone.  We have assigned speed dial #1 to a personal phone number and would like to change the name from "Voicemail".  Is this possible?  It was easy to edit on speed dials #2 - #9, but I don't see a way to do it for #1.

If you want feedback, Mom has a degenerative hearing loss of 70%.  It means that in a pristine laboratory environment she understands only 30% of words, even with the volume up.  Using the phone can be nearly impossible, but she's doing pretty well with the HAC setting on this phone and connecting it directly into her hearing aids with Bluetooth.  We're thrilled with this!  Also, we'd love a red button for emergency services.  We've set up speed dial #9 to call 911, yet in an emergency, it would be good to have something more obvious.  It could be something as simple as making the central zero key red and allowing it to be set as a speed dial.  The big numbers on this phone are excellent for her purpose.