Trying to build maelstrom on sparc4c (IPX) gives:

c++  -Inetlogic -I/usr/X11R6/include -I/usr/X11R6/include   -DSYSTEM=\"\" -DLIBDIR=\"/usr/X11R6/share/maelstrom\" -c myerror.cpp
myerror.cpp: In function `void myperror(char *)':
myerror.cpp:67: warning: implicit declaration of function `int strerror(...)'
c++  -o Maelstrom main.o framebuf.o v_framebuf.o x11_framebuf.o vga_framebuf.o  dga_framebuf.o fontserv.o sound.o Mac_Resource.o imagedump.o  init.o netlogic/netlogic.o  controls.o scores.o dialog.o fastrand.o netscore.o checksum.o  Utils.o shared.o myerror.o   -Wl,-R/usr/X11R6/lib -L/usr/X11R6/lib  -L/usr/X11R6/lib -lX11 -lXext -lXpm 
c++  -Inetlogic -I/usr/X11R6/include -I/usr/X11R6/include   -DSYSTEM=\"\" -DLIBDIR=\"/usr/X11R6/share/maelstrom\" -c Maelstrom_sound.cpp
In file included from Maelstrom_sound.cpp:22:
mixer.h:29: sun/audioio.h: No such file or directory
*** Error code 1

Stop.
*** Error code 1

Stop.
*** Error code 1

Stop.
*** Error code 1

Stop.

Any ideas?
Brad