I got the this error:
 
radius_xlat:  '122@domain.com'
rlm_sql (sql): sql_set_user escaped user --> '122@domain.com'
radius_xlat:  'VoIP_Radius '122@domain.com''
rlm_sql (sql): Reserving sql socket id: 16
radius_xlat:  ''
radius_xlat:  'VoIP_Radius '122@domain.com','',                                   '','192.168.1.1','''
rlm_sql: Failed to create the pair: Unknown value VOIP for attribute Service-Type
rlm_sql (sql): Error getting data from database
radius_xlat:  ''
in mssql.conf file i have
 
authorize_check_query = "VoIP_Radius '%{User-Name}'"
authorize_reply_query = "VoIP_Radius '%{User-Name}','%{Calling-Station-Id}',   \
                                '%{Called-Station-Id}','%{NAS-IP-Address}','%{h323-conf-id}','VOIP'"
 
 
I don't know sql server really much and I'm starting learning freeradius, so can some one explain me how "authorize_check_query" and "authorize_reply_query" dialogue with ms sql server?  
 
then, "Failed to create the pair" means there was a problem to get data from database I think but more exactely what does the error say ?
 
 
Thanks
Giuseppe