rewrite attribute in freeradius 3

Hi list, I'm trying to set up Freeradius (3.0.4 - as its whats included in the centos repo) for Eduroam. It should act as a proxy to an internal server.  Essentially, what I'm stuck at now is to rewrite the incoming User-Name attribute to remove the @domain postfix. In earlier versions I could use something like this: attr_rewrite rewrite_realm { attribute = User-Name searchin = packet searchfor = "^(.*)@adsl\.realm1$" replacewith = "%{1}" ignore_case = no new_attribute = no max_matches = 10 append = no } However, it seems its not supported in Freeradius 3: