where do I change the radius export behaviour?

[Kent Andersen]

when I use the radius export it sends

#added by freeside
username         Password = password

now this is a really good start, but unfortunatly its not enough to make my 
radius server happy..
for instance what I need is

#added by freeside (account name)
username         Password = "password"
Fall-Through = 1

and I need to append it to the start of the file prefferably instead of the 
current end of file behaviour it is doing now.

any ideas?

using freeside 1.4


Kent