ip restrictions in smb.conf question

[tony.brogan at unix1.trinity.ox.ac.uk]

i would like to restrict access to a samba server by ip address
i normally do this with the "hosts allow" parameter and can happily
restrict to just one class c network eg, 

hosts allow = 163.1.2.

but what if i want the above class c but not all of it eg, i want from
163.1.2.100 to 163.1.2.200

it doesnt seem practical to have a line:
hosts allow = 163.1.2.100, 163.1.2.101, etc

the hosts equiv parameter can take a filename as a parameter eg,
hosts equiv = /etc/hosts.equiv
but trying this with "hosts allow" just doesnt work. it lets everything 
through!

i have looked at the documentation but came up blank. any suggestions
would be most appreciated

many thanks

sincerely,

tony brogan