Hi,
This is possible.
1)Create extension of the hunt group members,while creating extension , uncheck "logged in to hunt group"
2)Create new soft key template for the huntgroup members to include "Hlogin" softkey.
3)Associate Extensions and softkey template created in the previous step to the target ip phones and restart the phones
4)Create new line group for the ACD and associate members extensions to this lune group.
5)Create new hunt group for the ACD and associate the line group vreated in the previous step.
6)Finally create hunt group pilot number and associate the unt group and reset the hunt group.
Now the target users can login to the hunt group using their "Hlogin" softkey avilable on their phones and will start receiving calls.
HTH
Tom