Which cell phone supports long rings on text message???

Hello, My company just purchased a Nokia 6085 for me to use. This phone is not meeting our needs, Does anyone know of a model (provider AT&T) that will meet our needs: Our main use for this phone will be to alert the user to text alerts that the phone will receive. The 6085 only rings 2x before it becomes silent. We need a phone that will wake up our on call person if they are sleeping. So, we need a phone that will ring loudly and long enough to wake someone up when the phone receives a text message. Thanks in advance for your help!

Nokia E51....It's All You Need

Thanks, Not Available from AT&T..