This is how I mount an SMB share in ESX, for example to copy files to/from and external USB drive:
esxcfg-firewall -enableService smbClient
mkdir /tmp/smbname
chkconfig netfs on
service netfs start
mount -t smbfs -o username=USER,password=PASSWORD //x.x.x.x/share /tmp/smbname/
rmdir /mnt/myshare
