--- a/src/lib/active_directory.h
+++ b/src/lib/active_directory.h
@@ -28,11 +28,11 @@
 | if there is a problem reading the config file, or
 |	AD_SERVER_CONNECT_FAILURE if a connection can't be made.
 */
-char *system_config_file;
-char *uri;
-char *binddn;
-char *bindpw;
-char *search_base;
+extern char *system_config_file;
+extern char *uri;
+extern char *binddn;
+extern char *bindpw;
+extern char *search_base;
 
 /* ad_get_error() returns a pointer to a string containing an
 | explanation of the last error that occured.