[horde] Filtering logon permission based on IP address

[Tim ODriscoll]

Dear All,

Is there a way to only allow a certain user group to logon from the  
local network, but to allow another user group to logon from external  
IP addresses as well as local?

I'm using OpenLDAP for authentication, so I'm wondering if there's a  
way to pass the IP address of the connecting client through to the  
LDAP authentication backend and then use an LDAP filter, but I'm not  
entirely sure how that filter would work yet, so I was wondering if  
there's another easier way through Horde..

Many thanks,

Tim