Port Scan results

Hi everyone, 

I'm new to Sophos but not new to the UTM world, 

I recently setup a SG115 at our office, and i ran the GRC port scan against the IP address.  The UTM successfully detected the port scan and logged the attempt, but there were multiple open ports showing on the port scan. Any idea if this is by design, or how i might be able to close them up / stealth them?

I know port 80 is probably going to be open for the Webadmin

Ports found to be OPEN were: 53, 80, 88, 139, 389, 464, 593, 
                             623, 636

Thanks!

Matt