Provisioning Cisco via FTP instead of TFTP

I am looking for this question to be answered, we are trying to make our system a bit more secure than TFTP by using FTP for provisioning these phones. I have not seen alot of info about it and the Cisco site is very cryptic as sure most of you are aware of. Basically I wanna switch from TFTP to FTP and would like to know if it is possible? and has anyone done it and some directions would be nice but am sure if i know its possible i can fiddle around tell i get it.
Thanks in advance