login from a shell script?????

Any help on this ..... its a bit urgent !!!!

Hi

Can anybody provide info about the following???

i want to issue su (switch user) command from within a shell script

how to take the password without user intervention from the shell script only???? i.e using apssword which is already stored ina variable within the shell script????

#!/usr/bin/sh

PASSWORD="hello"

su USER
// Here the password should be read from $PASSWORD variable.

Please tell me how it is possible??????

Thanks

Please provide any comments on the following. its highly urgent for me ......

I want to know also