There seemst do be a problem using icms_coreDataFilter::checkVar() for checking E-Mails. If you set
icms_core_DataFilter::checkVar($email, 'email', 1, 0);
the output should be myemail at example dot com, without checking the email against banned email-list. But (sometimes) it does check and give a blank page with Message:
Debug :: http://firstname.lastname@example.org
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