diff -ru spak-0.6b-orig/Makefile.LINUX spak-0.6b/Makefile.LINUX
--- spak-0.6b-orig/Makefile.LINUX	Mon Feb 16 01:51:55 1998
+++ spak-0.6b/Makefile.LINUX	Thu Feb 17 17:15:24 2000
@@ -11,6 +11,10 @@
 # before 5.4.33, you may need to uncomment the following:
 # COPT = -D__BSD_SOURCE
 #
+# If you are using glibc 2.0 or greater, you may need to uncomment 
+# the following:
+# COPT = -D_BSD_SOURCE
+#
 # For debugging, uncomment the following:
 # COPT = -g
 #
diff -ru spak-0.6b-orig/makeudp_sysconf.h spak-0.6b/makeudp_sysconf.h
--- spak-0.6b-orig/makeudp_sysconf.h	Sun Feb 15 22:44:20 1998
+++ spak-0.6b/makeudp_sysconf.h	Thu Feb 17 17:14:13 2000
@@ -21,10 +21,17 @@
 #endif  /* BSDI31 */
 
 #ifdef LINUX
+#if defined(__BSD_SOURCE) || defined(_BSD_SOURCE)
+#define UDP_FIELD_DEST uh_dport
+#define UDP_FIELD_CSUM uh_sum
+#define UDP_FIELD_LEN uh_ulen
+#define UDP_FIELD_SRC uh_sport
+#else /* ! defined(__BSD_SOURCE) || defined(_BSD_SOURCE) */
 #define UDP_FIELD_DEST dest
 #define UDP_FIELD_CSUM check
 #define UDP_FIELD_LEN len
 #define UDP_FIELD_SRC source
+#endif /* defined(__BSD_SOURCE) || defined(_BSD_SOURCE) */
 #endif  /* LINUX */
 
 #endif  /* __MAKEUDP_SYSCONF_H */