• You must remove any entries in the inetd.conf file for the old faxd.recv program and stop any running faxd.recv server processes.
• The new client-server protocol operates at port 4559 (+2 from the old ``fax'' port which defaulted to 4557). You may want to add a new service definition to a YP/NIS database (though you should be able to function without it.
• The new client-server protocol server, hfaxd(1M), is built by default with support for the old client-server protocol but the support must explicitly be enabled. If hfaxd is started up through the default shell script run by init(1M) and not by inetd(1M) then this happens automatically. Otherwise enabling support for the old protocol may require some manual configuration work. Consult the hfaxd(1M) manual page.
• faxq no longer accepts a -m option to specify modems to use in a send-only configuration. The faxmodem program should be used instead; consult the chapter on ``Server Setup and Basic Configuration'' and the manual pages for faxmodem(1M) and faxq(1M).
• The etc/hosts file on the server may contain passwords in v4.0 and hfaxd will not trust any information there unless the file is mode 0600. Since previous versions did not care what mode the file was it probably is publicly readable and hfaxd will deny client access until the mode is corrected.
• Completed jobs are removed asynchronously with a new faxqclean program; you will want to setup a cron entry to do this.
• The new faxsetup(1M) script must be run before a server machine can be used.

The remaining items are relevant to client and server installations:

• The old syntax ``host:modem'' for specifying a server and modem is no longer supported; the only syntax supported is ``modem[@host[:port]]''.
• The order of options on the command line to sendfax and sendpage is now important; consult the manual pages for details.

HylaFAX table of contents.