Add missing Kerberos checks

diff --git a/ConfigureChecks.cmake b/ConfigureChecks.cmake
index ee73507..fc57f08 100644
--- a/ConfigureChecks.cmake
+++ b/ConfigureChecks.cmake
@@ -433,6 +433,16 @@
 
 endif( )
 
+# check for krb5
+if( WITH_KRB5 )
+  pkg_search_module( KRB5 krb5 )
+  if( NOT KRB5_FOUND )
+      message(FATAL_ERROR "\nKerberos support was requested, but krb5 was not found on your system" )
+  endif( NOT KRB5_FOUND )
+  set( HAVE_KRB5 1 )
+  set( LIBTDELDAP_LIBRARIES "tdeldap" )
+endif( )
+
 # check for libr
 if( WITH_ELFICON )
   pkg_search_module( LIBR libr )
diff --git a/config.h.cmake b/config.h.cmake
index 6e27a27..d7d9b7a 100644
--- a/config.h.cmake
+++ b/config.h.cmake
@@ -36,6 +36,9 @@
 // libr
 #cmakedefine HAVE_ELFICON 1
 
+// krb5
+#cmakedefine HAVE_KRB5 1
+
 // libconfig
 #cmakedefine HAVE_LIBCONFIG 1
 #cmakedefine HAVE_LIBCONFIG_OLD_API 1