diff --git a/include/polarssl/pem.h b/include/polarssl/pem.h
index 1505401..e95dc10 100644
--- a/include/polarssl/pem.h
+++ b/include/polarssl/pem.h
@@ -3,7 +3,7 @@
  *
  * \brief Privacy Enhanced Mail (PEM) decoding
  *
- *  Copyright (C) 2006-2010, Brainspark B.V.
+ *  Copyright (C) 2006-2013, Brainspark B.V.
  *
  *  This file is part of PolarSSL (http://www.polarssl.org)
  *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
@@ -35,7 +35,7 @@
  * PEM data.
  * \{
  */
-#define POLARSSL_ERR_PEM_NO_HEADER_PRESENT                 -0x1080  /**< No PEM header found. */
+#define POLARSSL_ERR_PEM_NO_HEADER_FOOTER_PRESENT          -0x1080  /**< No PEM header or footer found. */
 #define POLARSSL_ERR_PEM_INVALID_DATA                      -0x1100  /**< PEM string is not as expected. */
 #define POLARSSL_ERR_PEM_MALLOC_FAILED                     -0x1180  /**< Failed to allocate memory. */
 #define POLARSSL_ERR_PEM_INVALID_ENC_IV                    -0x1200  /**< RSA IV is not in hex-format. */
@@ -43,6 +43,7 @@
 #define POLARSSL_ERR_PEM_PASSWORD_REQUIRED                 -0x1300  /**< Private key password can't be empty. */
 #define POLARSSL_ERR_PEM_PASSWORD_MISMATCH                 -0x1380  /**< Given private key password does not allow for correct decryption. */
 #define POLARSSL_ERR_PEM_FEATURE_UNAVAILABLE               -0x1400  /**< Unavailable feature, e.g. hashing/encryption combination. */
+#define POLARSSL_ERR_PEM_BAD_INPUT_DATA                    -0x1480  /**< Bad input parameters to function. */
 /* \} name */
 
 /**
@@ -77,7 +78,11 @@
  * \param data      source data to look in
  * \param pwd       password for decryption (can be NULL)
  * \param pwdlen    length of password
- * \param use_len   destination for total length used
+ * \param use_len   destination for total length used (set after header is
+ *                  correctly read, so unless you get
+ *                  POLARSSL_ERR_PEM_BAD_INPUT_DATA or
+ *                  POLARSSL_ERR_PEM_NO_HEADER_FOOTER_PRESENT, use_len is
+ *                  the length to skip)
  *
  * \return          0 on success, ior a specific PEM error code
  */