crontab doesn't start

[sinidr at libero.it]

Hi!I'm working with 2 linux, with 2 IP;I want make a copy of some files inside one directory to the other linux.I called a file scriptx.sh in the first linux and this is the body:
#!/bin/bash
rsync -avvz --delete --rsh=ssh --stats /home/copia/ root at 192.168.xxx.xx:/home/vrrp/dir/copia/

(xxx.xx are numbers...rights..only for security I crypted them)
ok, then I create the crontab file with crontab -e and this is it:

* * * * * /bin/scriptx.sh 

(every minute crontab should run...)
But it doesn't run.....
if I run this command from the line from the first linux is all ok,it runs(it asks me the password,I enter it,and then is all ok)
rsync -avvz --delete --rsh=ssh --stats /home/copia/ root at 192.168.xxx.xx:/home/vrrp/dir/copia/

where's the problem?why doesn't crontab work?
1000000 thanks