--- a/includes/gnutls/gnutls.h.in
+++ b/includes/gnutls/gnutls.h.in
@@ -251,7 +251,13 @@ extern "C"
      */
     GNUTLS_CERT_SIGNER_NOT_FOUND = 64,
     GNUTLS_CERT_SIGNER_NOT_CA = 128,
-    GNUTLS_CERT_INSECURE_ALGORITHM = 256
+    GNUTLS_CERT_INSECURE_ALGORITHM = 256,
+
+    /* Time verification.
+     */
+    GNUTLS_CERT_NOT_ACTIVATED = 512,
+    GNUTLS_CERT_EXPIRED = 1024
+
   } gnutls_certificate_status_t;

   typedef enum
diff --git a/includes/gnutls/x509.h b/includes/gnutls/x509.h
index 452247a..c750c87 100644
--- a/includes/gnutls/x509.h
+++ b/includes/gnutls/x509.h
@@ -481,7 +481,13 @@ extern "C"

     /* Allow certificates to be signed using the broken MD5 algorithm.
      */
-    GNUTLS_VERIFY_ALLOW_SIGN_RSA_MD5 = 32
+    GNUTLS_VERIFY_ALLOW_SIGN_RSA_MD5 = 32,
+
+    /* Disable checking of activation and expiration validity
+     * periods of certificate chains. Don't set this unless you
+     * understand the security implications.
+     */
+    GNUTLS_VERIFY_DISABLE_TIME_CHECKS = 64
   } gnutls_certificate_verify_flags;

   int gnutls_x509_crt_check_issuer (gnutls_x509_crt_t cert,
diff --git a/lib/gnutls_cert.c b/lib/gnutls_cert.c
index 94038eb..6b126bc 100644
--- a/lib/gnutls_cert.c
+++ b/lib/gnutls_cert.c
@@ -656,6 +656,8 @@ gnutls_certificate_verify_peers (gnutls_session_t session)
   * This function will return the peer's certificate expiration time.
   *
   * Returns: (time_t)-1 on error.
+  *
+  * Deprecated: gnutls_certificate_verify_peers2() now verifies expiration times.
   **/
 time_t
 gnutls_certificate_expiration_time_peers (gnutls_session_t session)
@@ -701,6 +703,8 @@ gnutls_certificate_expiration_time_peers (gnutls_session_t session)
   * This is the creation time for openpgp keys.
   *
   * Returns: (time_t)-1 on error.
+  *
+  * Deprecated: gnutls_certificate_verify_peers2() now verifies activation times.
   **/
 time_t
 gnutls_certificate_activation_time_peers (gnutls_session_t session)
diff --git a/lib/x509/verify.c b/lib/x509/verify.c
index 4b1252e..538d96e 100644
--- a/lib/x509/verify.c.cve-2009-1417	2009-05-01 20:16:30.000000000 +0200
+++ b/lib/x509/verify.c	2009-05-01 20:24:19.000000000 +0200
@@ -417,6 +417,31 @@
     }
 #endif
 
+  /* Check activation/expiration times
+   */
+  if (!(flags & GNUTLS_VERIFY_DISABLE_TIME_CHECKS))
+    {
+      time_t t, now = time (0);
+
+      for (i = 0; i < clist_size; i++)
+	{
+	  t = gnutls_x509_crt_get_activation_time (certificate_list[i]);
+	  if (t == (time_t) -1 || now < t)
+	    {
+	      status |= GNUTLS_CERT_NOT_ACTIVATED;
+	      status |= GNUTLS_CERT_INVALID;
+	      return status;
+	    }
+
+	  t = gnutls_x509_crt_get_expiration_time (certificate_list[i]);
+	  if (t == (time_t) -1 || now > t)
+	    {
+	      status |= GNUTLS_CERT_EXPIRED;
+	      status |= GNUTLS_CERT_INVALID;
+	      return status;
+	    }
+	}
+    }
   /* Verify the certificate path (chain) 
    */
   for (i = clist_size - 1; i > 0; i--)
@@ -734,9 +759,6 @@
   * @verify: will hold the certificate verification output.
   *
   * This function will try to verify the given certificate list and return its status.
-  * Note that expiration and activation dates are not checked
-  * by this function, you should check them using the appropriate functions.
-  *
   * If no flags are specified (0), this function will use the 
   * basicConstraints (2.5.29.19) PKIX extension. This means that only a certificate 
   * authority is allowed to sign a certificate.
diff --git a/src/common.c b/src/common.c
index cc50888..c60900b 100644
--- a/src/common.c
+++ b/src/common.c
@@ -427,6 +427,10 @@ print_cert_vrfy (gnutls_session_t session)
     {
       if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
 	printf ("- Peer's certificate issuer is unknown\n");
+      if (status & GNUTLS_CERT_NOT_ACTIVATED)
+	printf ("- Peer's certificate chain uses not yet valid certificate\n");
+      if (status & GNUTLS_CERT_EXPIRED)
+	printf ("- Peer's certificate chain uses expired certificate\n");
       if (status & GNUTLS_CERT_INVALID)
 	printf ("- Peer's certificate is NOT trusted\n");
       else