7 calls to valid_email_address() in Drupal 6

comment_validate in modules/comment/comment.module

Validate comment data.

contact_admin_edit_validate in modules/contact/contact.admin.inc

Validate the contact category edit page form submission.

contact_mail_page_validate in modules/contact/contact.pages.inc

Validate the site-wide contact page form submission.

contact_user_page in modules/contact/contact.pages.inc

Personal contact page.

system_send_email_action_validate in modules/system/system.module

Validate system_send_email_action form submissions.

update_settings_validate in modules/update/update.settings.inc

Validation callback for the settings form.

user_validate_mail in modules/user/user.module