Unfortunately I didn't find a way to submit a bugfix yet.

Just replace the $_ibanregex in Zend_Validate_Iban with these lines:

protected $_ibanregex = array(
    'AD' => '/^AD[0-9]{2}[0-9]{8}[A-Z0-9]{12}$/',
    'AE' => '/^AE[0-9]{2}[0-9]{3}[0-9]{16}$/',
    'AL' => '/^AL[0-9]{2}[0-9]{8}[A-Z0-9]{16}$/',
    'AT' => '/^AT[0-9]{2}[0-9]{5}[0-9]{11}$/',
    'AZ' => '/^AZ[0-9]{2}[0-9]{4}[A-Z0-9]{20}$/',
    'BA' => '/^BA[0-9]{2}[0-9]{6}[0-9]{10}$/',
    'BE' => '/^BE[0-9]{2}[0-9]{3}[0-9]{9}$/',
    'BG' => '/^BG[0-9]{2}[A-Z]{4}[0-9]{4}[0-9]{2}[A-Z0-9]{8}$/',
    'BH' => '/^BH[0-9]{2}[A-Z]{4}[A-Z0-9]{14}$/',
    'BR' => '/^BR[0-9]{2}[0-9]{8}[0-9]{5}[0-9]{10}[A-Z]{1}[A-Z0-9]{1}$/',
    'CH' => '/^CH[0-9]{2}[0-9]{5}[A-Z0-9]{12}$/',
    'CR' => '/^CR[0-9]{2}[0-9]{3}[0-9]{14}$/',
    'CS' => '/^CS[0-9]{2}[0-9]{3}[0-9]{15}$/',
    'CY' => '/^CY[0-9]{2}[0-9]{8}[A-Z0-9]{16}$/',
    'CZ' => '/^CZ[0-9]{2}[0-9]{4}[0-9]{16}$/',
    'DE' => '/^DE[0-9]{2}[0-9]{8}[0-9]{10}$/',
    'DK' => '/^DK[0-9]{2}[0-9]{4}[0-9]{10}$/',
    'DO' => '/^DO[0-9]{2}[A-Z0-9]{4}[0-9]{20}$/',
    'EE' => '/^EE[0-9]{2}[0-9]{4}[0-9]{12}$/',
    'ES' => '/^ES[0-9]{2}[0-9]{8}[0-9]{12}$/',
    'FR' => '/^FR[0-9]{2}[0-9]{10}[A-Z0-9]{11}[0-9]{2}$/',
    'FI' => '/^FI[0-9]{2}[0-9]{6}[0-9]{8}$/',
    'FO' => '/^FO[0-9]{2}[0-9]{4}[0-9]{9}[0-9]{1}$/',
    'GB' => '/^GB[0-9]{2}[A-Z]{4}[0-9]{14}$/',
    'GE' => '/^GE[0-9]{2}[A-Z]{2}[0-9]{16}$/',
    'GI' => '/^GI[0-9]{2}[A-Z]{4}[A-Z0-9]{15}$/',
    'GL' => '/^GL[0-9]{2}[0-9]{4}[0-9]{9}[0-9]{1}$/',
    'GR' => '/^GR[0-9]{2}[0-9]{7}[A-Z0-9]{16}$/',
    'GT' => '/^GT[0-9]{2}[A-Z0-9]{4}[A-Z0-9]{20}$/',
    'HR' => '/^HR[0-9]{2}[0-9]{7}[0-9]{10}$/',
    'HU' => '/^HU[0-9]{2}[0-9]{7}[0-9]{1}[0-9]{15}[0-9]{1}$/',
    'IE' => '/^IE[0-9]{2}[A-Z0-9]{4}[0-9]{6}[0-9]{8}$/',
    'IL' => '/^IL[0-9]{2}[0-9]{3}[0-9]{3}[0-9]{13}$/',
    'IS' => '/^IS[0-9]{2}[0-9]{4}[0-9]{18}$/',
    'IT' => '/^IT[0-9]{2}[A-Z]{1}[0-9]{10}[A-Z0-9]{12}$/',
    'KW' => '/^KW[0-9]{2}[A-Z]{4}[0-9]{3}[0-9]{22}$/',
    'KZ' => '/^KZ[A-Z]{2}[0-9]{2}[0-9]{3}[A-Z0-9]{13}$/',
    'LB' => '/^LB[0-9]{2}[0-9]{4}[A-Z0-9]{20}$/',
    'LI' => '/^LI[0-9]{2}[0-9]{5}[A-Z0-9]{12}$/',
    'LU' => '/^LU[0-9]{2}[0-9]{3}[A-Z0-9]{13}$/',
    'LT' => '/^LT[0-9]{2}[0-9]{5}[0-9]{11}$/',
    'LV' => '/^LV[0-9]{2}[A-Z]{4}[A-Z0-9]{13}$/',
    'MC' => '/^MC[0-9]{2}[0-9]{5}[0-9]{5}[A-Z0-9]{11}[0-9]{2}$/',
    'MD' => '/^MD[0-9]{2}[A-Z0-9]{20}$/',
    'ME' => '/^ME[0-9]{2}[0-9]{3}[0-9]{13}[0-9]{2}$/',
    'MK' => '/^MK[0-9]{2}[A-Z]{3}[A-Z0-9]{10}[0-9]{2}$/',
    'MR' => '/^MR13[0-9]{5}[0-9]{5}[0-9]{11}[0-9]{2}$/',
    'MU' => '/^MU[0-9]{2}[A-Z]{4}[0-9]{2}[0-9]{2}[0-9]{12}[0-9]{3}[A-Z]{2}$/',
    'MT' => '/^MT[0-9]{2}[A-Z]{4}[0-9]{5}[A-Z0-9]{18}$/',
    'NL' => '/^NL[0-9]{2}[A-Z]{4}[0-9]{10}$/',
    'NO' => '/^NO[0-9]{2}[0-9]{4}[0-9]{7}$/',
    'PK' => '/^PK[0-9]{2}[A-Z]{4}[0-9]{16}$/',
    'PL' => '/^PL[0-9]{2}[0-9]{8}[0-9]{16}$/',
    'PS' => '/^PS[0-9]{2}[A-Z]{4}[0-9]{21}$/',
    'PT' => '/^PT[0-9]{2}[0-9]{8}[0-9]{13}$/',
    'RO' => '/^RO[0-9]{2}[A-Z]{4}[A-Z0-9]{16}$/',
    'RS' => '/^RS[0-9]{2}[0-9]{3}[0-9]{13}[0-9]{2}$/',
    'SA' => '/^SA[0-9]{2}[0-9]{2}[A-Z0-9]{18}$/',
    'SE' => '/^SE[0-9]{2}[0-9]{3}[0-9]{17}$/',
    'SI' => '/^SI[0-9]{2}[0-9]{5}[0-9]{8}[0-9]{2}$/',
    'SK' => '/^SK[0-9]{2}[0-9]{4}[0-9]{16}$/',
    'SM' => '/^SM[0-9]{2}[A-Z]{1}[0-9]{5}[0-9]{5}[A-Z0-9]{12}$/',
    'TN' => '/^TN[0-9]{2}[0-9]{5}[0-9]{15}$/',
    'TR' => '/^TR[0-9]{2}[0-9]{5}[A-Z0-9]{17}$/',
    'VG' => '/^VG[0-9]{2}[A-Z]{4}[0-9]{16}$/'
);

Patch attached.

Not quite shure if I can commit the patch by myself and how the workflow is. Seems that Thomas is responsible for the Validate Component. Can you manage this?

@[~billomat] Thomas no longer works for the ZF project.