OS: RHEL4 AS4

I want to mount a win3004 network-shared volume on my linux box via autofs.
I did as follows.

1> Add the following line under /etc/auto.master to create a mount map.

/mnt /etc/auto.direct

2> Create /etc/auto.direct as follows.
lab01 -fstype=cifs,credentials=/etc/secret.file ://winbox-ip/net-vol

/etc/secret.file includes the username/password to access the winbox net-vol.

3> start autofs by "#service autofs start"


Problem:
I tried to move to /mnt/lab01 but it shows "/mnt/lab01: No such device and address". Then, I tried to mount the net-vol manually as follows and it works fine.

# mount -t cifs -o credentials=/etc/secret.file //winbox-ip/net-vol /mnt/lab01

Also, I tail the /var/log/messages and it shows as follows.

======================================================
automount[12157]: lookup(program):failed
Apr 24 17:39:32 localhost automount[12157]: failed to mount /mnt/lab01
======================================================

Kindly please give me some ideas to troubleshoot the autofs + cifs problem.