The 68k Freeciv (except ancient versions) doesn't work so well with OS4; especially Roadshow causes problems. That's why I chose to put together an English-only server (ie. no gettext) that seems to work.

Installing Freeciv: Simply copy civserver to your Freeciv directory, rename the old first if you want. If you do not have the game yet, you can get it from
http://www.sebastianbauer.info/index.php?page=amiga/freeciv

Compiling Freeciv: The included config.h and Makefile were used to build the server, but they may not be good for the client. vbcc and newlib is used, which is why amigaserver.c is not. The source code is on ftp.freeciv.org

 PERMSSN    UID  GID    PACKED    SIZE  RATIO METHOD CRC     STAMP          NAME
---------- ----------- ------- ------- ------ ---------- ------------ -------------
[generic]               389985 1087820  35.9% -lh5- f3fb Mar 20  2006 civserver
[generic]                 7009   18007  38.9% -lh5- fa00 Jan 22  2003 copying
[generic]                 2524    8734  28.9% -lh5- 90af Mar 20  2006 amiga/config.h
[generic]                 4671   25985  18.0% -lh5- 3598 Mar 20  2006 amiga/Makefile
---------- ----------- ------- ------- ------ ---------- ------------ -------------
 Total         4 files  404189 1140546  35.4%            Mar 21  2006