Secured FTP?

[Peczoli Zoltan <pocok@pcdome.hu>]

hi,

Unfortunately I haven't found a solution to the following yet:

I need a secure(1) file transfer method (passwords and data travelling
encrypted through the network) which retrieves the authentication info
from a file other than /etc/shadow or etc/passwd but a file of the same
format(2) and where users are restricted to manipulate only in their home
directories(3).

/I managed to set up proftpd, it does (2) and (3) but not the most
important (1)/

Is there a way to do these using debian packages?
If not, non-debian-specific solutions are welcome, too :)

Thanx:
          pocok