ISG DHCP relay

[Igor Smitran]

I am sorry for contacting list for my problem, but i have searched for 
more than 15 days trying to find the solution with no success:

1. i have a cisco ISG with DHCP relay that points to freeradius
2. freeradius will send access accept or access reject based on mac 
address, nas ip etc.

this scenario works ok for CPE devices, but not for CM devices because 
CM devices need TFTP server name and TFTP file name. I am unable to find 
right reply message format. So, my problem is BOOTP part. Is there any 
way to send those data to ISG so that ISG can combine those data and 
send it to CM device?
Again, i am sorry for asking this question here but it is partially tied 
to freeradius functionality. I hope there is someone on this list that 
has more experience with ISG and freeradius to point me to right direction.

Thank you...