--- configure.in.orig	Wed Aug 19 21:29:58 1998
+++ configure.in	Sat Jun 17 02:46:57 2000
@@ -41,7 +41,7 @@
 dnl Checks for header files.
 AC_HEADER_DIRENT
 AC_HEADER_STDC
-AC_CHECK_HEADERS(fcntl.h sys/time.h unistd.h sys/types.h sys/stat.h re_comp.h net/errno.h getopt.h sys/param.h)
+AC_CHECK_HEADERS(fcntl.h ndbm.h sys/time.h unistd.h sys/types.h sys/stat.h re_comp.h net/errno.h getopt.h sys/param.h)
 AC_CHECK_FUNCS(flock)
 
 dnl Checks for typedefs, structures, and compiler characteristics.