How do i make input box a textarea box for profile fields?

Im making a about me profile field by editing the yahoo profile field i have renamed it using lang and have made it able to store more data via database however how can i now make it so its nota input box but textarea so not all on one line?

Any help please

Iv tried just changing the input id= to textarea and that but that displayed a textarea that doesnt save to profile and displays inside it a whol load of html code and stuff.. any help?

thanks