syntax for network specification in admit?

If I try to specify a set of allowed hosts, using the syntax
admit   => { "192.168.4/24"}

my hosts don't match.

If I explicitly specify a host:
admit   => { "192.168.4.22"}

then the host can connect.

I also tried pattern matching syntax
dmit   => { "192\.168\.4.\.*"}
which didn't work either.


What's the proper syntax to specify that I trust all hosts on a subnet?