Question : ODBC connection failing

We made some network changes recently and 2 days after the changes were implemented a series of DTS jobs started to fail with a timeout error. Each of these jobs was attempting to connect to a Solaris server using an Informix ODBC driver. We pulled everything back so that the network changes were reversed but the ODBC connection is still failing. The error message is 81015.

Answer : ODBC connection failing

What was the nature of "changes implemented"?
If this was MDAC update - you have to use Informix CSDK later than MDAC.
If you have changed IP or port - it has to be refelcted in hosts and services files.
Error message makes no sense, not Informix or ODBC one for sure.

Can you provide IDS and CSDK versions?