Use all three arguments of AC_DEFINE.

configure.in

-dnl $Id: configure.in,v 1.81 2002/04/11 20:16:55 byers Exp $
+dnl $Id: configure.in,v 1.82 2002/06/13 22:47:53 ceder Exp $
 dnl Configuration for LysKOM
 dnl Copyright (C) 1993-2002  Lysator Academic Computer Association.
 dnl
@@ -18,7 +18,7 @@ dnl Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 dnl
 dnl Please mail bug reports to bug-lyskom@lysator.liu.se. 
 dnl
-AC_REVISION($Revision: 1.81 $)
+AC_REVISION($Revision: 1.82 $)
 AC_PREREQ(2.53)
 AC_INIT([lyskom-server], [2.0.6])
 AC_CONFIG_SRCDIR([src/server/lyskomd.h])
@@ -130,20 +130,28 @@ then]
 AC_SUBST(TRACED_ALLOCATIONS)
 [if test "$use_traced_allocations" = "yes"
 then]
-	AC_DEFINE(TRACED_ALLOCATIONS)
+	AC_DEFINE([TRACED_ALLOCATIONS], 1,
+	[Should all allocations be traced?  See src/server/ram-smalloc.c.])
 [fi]
 
 AC_SUBST(DEBUG_CALLS)
 [if test "$use_debug_calls" = "yes"
 then]
-        AC_DEFINE(DEBUG_CALLS)
+        AC_DEFINE([DEBUG_CALLS], 1, 
+	          [Include special debug requests.  Don't use this on
+		   a production server.  The debug requests are
+		   insecure.  The test suite uses these calls if they
+		   are available to increase the coverage.])
         AC_CHECK_FUNCS(mallinfo)
 [fi]
 
 [if test "$use_gcov" = "yes" -a -n "$GCC"; then]
         CMOD_CHECK_CC_OPT([-ftest-coverage], [test_coverage])
         CMOD_CHECK_CC_OPT([-fprofile-arcs], [profile_arcs])
-        AC_DEFINE(AVOID_ABORTS)
+        AC_DEFINE([AVOID_ABORTS], 1, 
+	          [This should be defined if you want gcov
+		  statistics. It replaces some aborts with exits so
+		  coverage data is output.])
 [fi]
 
 [if test -n "$opt_level" -a "$opt_level" != "yes" ; then
@@ -181,7 +189,8 @@ AC_TRY_COMPILE([#include <signal.h>],
   AC_MSG_RESULT($kom_cv_struct_sigaction)
 [fi]
 [if test $kom_cv_struct_sigaction = yes ; then]
-  AC_DEFINE(HAVE_STRUCT_SIGACTION)
+  AC_DEFINE([HAVE_STRUCT_SIGACTION], 1, 
+            [Define if struct sigaction is available.])
 [fi]
 
 AC_C_CONST
@@ -199,7 +208,9 @@ AC_CACHE_CHECK([if sig_atomic_t exists], kom_cv_type_sig_atomic_t,
 	[kom_cv_type_sig_atomic_t=no])])
 [if test $kom_cv_type_sig_atomic_t = no
 then]
-    AC_DEFINE(sig_atomic_t, int)
+    AC_DEFINE([sig_atomic_t], [int], 
+              [Define this to a type that can be changed atomically
+	      from a signal handler if your OS lacks sig_atomic_t.])
 [fi]
 dnl
 # FIXME (bug 209): is this needed now that we use AM_C_PROTOTYPES?
@@ -220,7 +231,8 @@ AC_TRY_LINK(
 [kom_cv_sys_hpux_source=no])])])
 AC_MSG_RESULT($kom_cv_sys_hpux_source)
 [if test $kom_cv_sys_hpux_source = yes ; then]
-  AC_DEFINE(_HPUX_SOURCE)
+  AC_DEFINE([_HPUX_SOURCE], 1, [Define if on HPUX])
+
 [fi]
 dnl
 dnl
@@ -232,7 +244,8 @@ __attribute__ ((format (printf, 1, 2)));],,
 [kom_cv_c_attribute_format_printf=no])])
 AC_MSG_RESULT($kom_cv_c_attribute_format_printf)
 [if test $kom_cv_c_attribute_format_printf = yes ; then]
-  AC_DEFINE(HAVE_ATTRIBUTE_FORMAT_PRINTF)
+  AC_DEFINE([HAVE_ATTRIBUTE_FORMAT_PRINTF], 1, 
+            [Define if your compiler supports __attribute__ in printf.])
 [fi]
 AC_MSG_CHECKING([if the compiler understands __attribute__ ((__noreturn__))])
 AC_CACHE_VAL([kom_cv_c_attribute_noreturn],
@@ -242,7 +255,8 @@ __attribute__ ((__noreturn__));],,
 [kom_cv_c_attribute_noreturn=no])])
 AC_MSG_RESULT($kom_cv_c_attribute_noreturn)
 [if test $kom_cv_c_attribute_noreturn = yes ; then]
-  AC_DEFINE(HAVE_ATTRIBUTE_NORETURN)
+  AC_DEFINE([HAVE_ATTRIBUTE_NORETURN], 1,
+            [Define if your compiler supports __attribute__ ((noreturn)).])
 [fi]
 AC_PROG_INSTALL
 AC_PROG_RANLIB
@@ -288,10 +302,12 @@ dnl
 dnl I don't know how to test for buggy inet_ntoa functions
 dnl programmatically, but the supplied substitute should always work,
 dnl so we define BUGGY_INET_NTOA unconditionally.
-AC_DEFINE(BUGGY_INET_NTOA)
+AC_DEFINE([BUGGY_INET_NTOA], 1, 
+          [Define if your OS has buggy inet_ntoa. If you don't know,
+	   define this.])
 dnl
 dnl Unencrypted passwords are no longer supported.
-AC_DEFINE(ENCRYPT_PASSWORDS)
+AC_DEFINE([ENCRYPT_PASSWORDS], 1, [Define if you want encrypted passwords])
 dnl
 dnl Tests for GNU getopt (used in dbck)
 AC_CHECK_HEADERS(alloca.h)