[Tokend-Dev] Spanish ID card - PKCS11.tokend

Hi all I have been trying to use the PKCS11.tokend in order to integrate the Spanish id card with the keychain services. Unfortunately, the certificates saved in the Spanish id card are protected by a pin so the initial "discover" stage performed by the PKCS11.tokend doesn't find any valid certificate. Can somebody explain how I can request the pin before the tokend call to C_FindObjects function?. Thanks, Marcos.