INFORMIX x DELPHI

Is there anybody using Informix DS 7.23 on AIX 4 and DELPHI? The connection error is -956: Client host or user (valid_user@xxx.xxx.xxx.xxx.xx) is not trusted by the server. The problem is: the valid_user is valid but not the @xxx.xxx.xxx.xxx.xx. The solution that Inrformix Find Error help give me is: The desired database server does not consider the client computer or your user ID trusted. Ask the system administrator to include the client computer as a trusted host and/or your user id as a trusted user in the /etc/hosts.equiv file on the server computer or in the .rhosts file in your home directory on the server computer. See the UNIX manual pages on HOSTS.EQUIV(5) for more information. Alternatively, you can explicitly specify your user name and password in the USER clause of a CONNECT statement or in the .netrc file in your home directory on the client computer. See the Informix Guide to SQL: Syntax for information on the CONNECT statement, and the UNIX manual pages regarding NETRC(5) for information on the .netrc file. This message appears with Version 6.0 and later. But, using /etc/hosts.equiv or .netrc the unix adm said the system can be unsecure. What is the best solution?