Contextual mapping of LDAP attributes

Hey guys, I have another question. Again I haven't found nice solution yet. How can I map different LDAP attribute to the same RADIUS attribute depending on some access request parameters? E.g. in my LDAP I have: - adslVirtualRouterName - xdslVirtualRouterName - xxxVirtualName I'd like to map this LDAP attribute to RADIUS ERX-Virtual-Router-Name depending on e.g. NAS-IP-Address. One solution would be declare some additional variables in /etc/raddb/dictionary and just map it in ldap module update section. But is there better solution? thanks, Krzysztof