I developed a custom form with FAPI and added a block for it.
Block is included only on one specific page (basic node).
When user submits this form it should redirect user to external site (URL is a return value from another external site). For this purpose I've used $form['redirect'] which was working when this form was used as standalone page. In block it won't redirect and instead the same page is loaded.
I tried other methods too for redirecting such as php header location and drupal_goto but none of them work.
Perhaps there is something node level overriding that prevents the form redirect?
EDIT:
Block is a very basic implementation on code level. API based hook_info and hook_view functions accompanied with custom content function (which returns form markup:drupal_get_form('my_form')).
The redirect is defined on hook_form_submit($form, &$form_state) in which it first makes two calls to external web services and based on return values it either redirects or shows message:
// Debug shows that this evaluates true
if (!filter_var($webservice1, FILTER_VALIDATE_URL) === false) {
$form_state['redirect'] = $webservice1;
} else if ($webservice1 == 'ok' && $webservice2 == 'ok') {
drupal_set_message(theme_item_list($formvalues),'status');
} else {
drupal_set_message('Error', 'error');
}