Index: src/auth/db-ldap.c
===================================================================
RCS file: /var/lib/cvs/dovecot/src/auth/db-ldap.c,v
retrieving revision 1.41.2.18
diff -u -r1.41.2.18 db-ldap.c
--- src/auth/db-ldap.c	19 Jan 2007 15:27:42 -0000	1.41.2.18
+++ src/auth/db-ldap.c	2 Apr 2007 14:05:31 -0000
@@ -41,6 +41,8 @@
 #  define LDAP_OPT_SUCCESS LDAP_SUCCESS
 #endif
 
+#define LDAP_TIMEOUT_SECS (60*5)
+
 #define DEF(type, name) \
 	{ type, #name, offsetof(struct ldap_settings, name) }
 
@@ -307,6 +309,8 @@
 	LDAPMessage *res;
 	int ret, msgid;
 
+	conn->last_io = ioloop_time;
+
 	for (;;) {
 		if (conn->ld == NULL)
 			return;
@@ -472,6 +476,15 @@
 	net_set_nonblock(conn->fd, TRUE);
 }
 
+static void ldap_timeout(void *context)
+{
+	struct ldap_connection *conn = context;
+
+	if (conn->last_io + LDAP_TIMEOUT_SECS < ioloop_time &&
+	    hash_size(conn->requests) == 0)
+		ldap_conn_close(conn, FALSE);
+}
+
 int db_ldap_connect(struct ldap_connection *conn)
 {
 	unsigned int ldap_version;
@@ -560,6 +573,7 @@
 	}
 
 	conn->io = io_add(conn->fd, IO_READ, ldap_input, conn);
+	conn->to = timeout_add(1000, ldap_timeout, conn);
 	return 0;
 }
 
@@ -592,6 +606,8 @@
 	conn->connected = FALSE;
 	conn->binding = FALSE;
 
+	if (conn->to != NULL)
+		timeout_remove(&conn->to);
 	if (conn->io != NULL)
 		io_remove(&conn->io);
 
Index: src/auth/db-ldap.h
===================================================================
RCS file: /var/lib/cvs/dovecot/src/auth/db-ldap.h,v
retrieving revision 1.20.2.9
diff -u -r1.20.2.9 db-ldap.h
--- src/auth/db-ldap.h	19 Jan 2007 15:19:29 -0000	1.20.2.9
+++ src/auth/db-ldap.h	2 Apr 2007 14:05:31 -0000
@@ -57,6 +57,8 @@
 	LDAP *ld;
 	int fd; /* only set when connected/connecting */
 	struct io *io;
+	struct timeout *to;
+	time_t last_io;
 
 	struct hash_table *requests;
 	struct ldap_request *delayed_requests_head, *delayed_requests_tail;