diff --git a/configure.in b/configure.in
index eb089abb5..d01d5467e 100644
--- a/configure.in
+++ b/configure.in
@@ -141,6 +141,29 @@ if test "$with_krb4" != "no"; then
 	AC_FIND_FUNC(krb_enable_debug)
 	AC_FIND_FUNC(krb_disable_debug)
 	AC_FIND_FUNC(krb_get_our_ip_for_realm)
+	AC_FIND_FUNC(krb_kdctimeofday)
+	AH_BOTTOM(
+	[#ifndef HAVE_KRB_KDCTIMEOFDAY
+#define krb_kdctimeofday(X) gettimeofday((X), NULL)
+#endif])
+	AC_FIND_FUNC(krb_get_kdc_time_diff)
+	AH_BOTTOM(
+	[#ifndef HAVE_KRB_GET_KDC_TIME_DIFF
+#define krb_get_kdc_time_diff() (0)
+#endif])
+	AC_CACHE_CHECK(for KRB_SENDAUTH_VERS,
+		ac_cv_func_krb_sendauth_vers,
+		[AC_TRY_COMPILE([#include <krb.h>],[
+		char *x = KRB_SENDAUTH_VERS],
+		ac_cv_func_krb_sendauth_vers=yes,
+		ac_cv_func_krb_sendauth_vers=no)
+	])
+	if test "$ac_cv_func_krb_sendauth_vers" != yes; then
+		AC_DEFINE(KRB_SENDAUTH_VERS, ["AUTHV0.1"],
+			[This is the krb4 sendauth version.])
+		AC_DEFINE(KRB_SENDAUTH_VLEN, 8],
+			[Length of KRB_SENDAUTH_VERS.])
+	fi
 	AC_CACHE_CHECK(for krb_mk_req with const arguments,
 		ac_cv_func_krb_mk_req_const,
 		[AC_TRY_COMPILE([#include <krb.h>
@@ -152,7 +175,7 @@ if test "$with_krb4" != "no"; then
 	])
 	if test "$ac_cv_func_krb_mk_req_const" = "yes"; then
 		AC_DEFINE(KRB_MK_REQ_CONST, 1,
-			[Define if krb_mk_req takes cons char *])
+			[Define if krb_mk_req takes const char *])
 	fi
 
 	LIBS="$save_LIBS"