MX V5.1-A ECO 01, 06-JAN-2000

Change description:

   * Fix for host name lookups on systems that
     do not use the Domain Name System, to eliminate
     NODNSRESPONSE errors.

Installation:

    1. Copy the appropriate image (VAX or Alpha) to MX_EXE:

          $ COPY MX_SMTP.{AXP|VAX}_EXE MX_EXE:*.EXE

    2. Shutdown and restart the SMTP server:

    	  $ MCR MX_EXE:MCP SHUTDOWN SMTP
          $ @SYS$STARTUP:MX_STARTUP SMTP

* If you have a mixed VMScluster with both VAX and Alpha systems,
  you will need both images - one for each architecture.

* If you run the SMTP agent on multiple nodes in your
  cluster, you should execute step 2 on each of the nodes currently
  running the SMTP agent.