GOOGLE

ADDALLOW host or hostmask
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This Function allows you to set hosts which may connect to your bouncer.
On default, * is set to be allowed to connect to the bouncer. You would
have to delete that entry first to set your own more restricted host
allows for the bouncer.
Example 
/ADDALLOW host22.mydomain.com
would allow that specific host to connect.
/ADDALLOW *.mydomain.com
would allow all hosts from mydomain.com.
You can use the wildcards ? and * in your definition.
Remember that also linked hosts have to be added in the host allowance.
See also: DELALLOW LISTALLOW