how to prevent rsyncd reverse lookups

[Mi]

Is there a way to prevent rsyncd from doing reverse IP lookups on 
connecting clients? I didn't find any config option for this.

There are several situations where these lookups will always fail and 
uselessly slow down the connection. One such situation is when using 
rsync on a small home network to do backups to a NAS.

Is there a solution to this, without telling people to set up a local 
DNS server or use a different home router (which is generally also the 
DNS server)?

Thanks,

MI