Problems compiling libgtop 0.99.8

[David Pinson <dpinson materials unsw edu au>]

I've built everything (almost) else without problems, 
except the *gtop set of packages since when I try to
build libgtop I get:

gcc -DHAVE_CONFIG_H -I. -I. -I../.. -D_IN_LIBGTOP -D_GNU_SOURCE
-DGLIBTOP_NAMES
-I../.. -I../.. -I../../sysdeps/linux -I../../include -I../../intl
-I/usr/local/gnome/include -DNEED_GNOMESUPPORT_H
-I/usr/local/gnome/lib/gnome-libs/include
-I/usr/local/gnome/lib/glib/include -I/usr/X11R6/include
-I/usr/local/gnome/lib/glib/include -I/usr/local/gnome/include -g -O2
-Wall -Wno-unused -I/usr/X11R6/include -DGLIBTOP_GUILE
-DGLIBTOP_GUILE_NAMES -I/usr/local/include
-DGTOPLOCALEDIR=\"/usr/local/gnome/share/locale\"
-DLIBGTOP_VERSION=\"0.99.8\" -DLIBGTOP_SERVER_VERSION=\"3\"
-DLIBGTOP_SERVER=\"/usr/local/gnome/bin/libgtop_server\" -g -O2 -Wall
-Wno-unused -c -fPIC -DPIC netload.c -o netload.lo
In file included from netload.c:46:
/usr/include/linux/ip_fw.h:253: field `timer' has incomplete type
make[3]: *** [netload.lo] Error 1
make[3]: Leaving directory
`/usr/local/src/gnome/builddir/libgtop-0.99.8/sysdeps/linux'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory
`/usr/local/src/gnome/builddir/libgtop-0.99.8/sysdeps'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/usr/local/src/gnome/builddir/libgtop-0.99.8'
make: *** [all-recursive-am] Error 2

I running kernel 2.0.36 on a slackware 3.6 based system.

I would appreciate any clues

**************************************************
*  David Pinson                                  *
*  dpinson@materials.unsw.edu.au                 *
*  School of Materials Science and Engineering   *
*  University of New South Wales, Australia      *
**************************************************