Using the WMI Event Watcher Task on FTP

I am wondering if I can use a WMI Event Watcher (SSIS in SQL Server 2008) to monitor a FTP Directory, and if so, what will a sample WQL Query look like to do that?

I saw couple of examples where WMI is used to watch files in a particular windows folder but my requirement is I need to monitor an ftp site for the file and when the file arrives I need to email ( use send mail task) the concerned users. 

Please advice as to how can we monitor ftp site using SSIS?

Thanks

EVA05