Very thankx for reply @elpatron,
I just thought that... to make function to show HTML output, but how i replace with this code as I use rander form and my current syntex is like below which i want to convert in clickable link.
public function renderForm()
{
$this->fields_form = array(
'legend' => array(
'title' => $this->l('Contact Request'),
),
....
....
array(
'type' => 'textarea', // Change might be here
'label' => $this->l('Url:'),
'name' => 'url',
'cols' => 30,
'rows' => 4,
'required' => true,
'desc' => $this->l('Product Url'),
),
Here type is given as 'textarea', So, type will be html or anything else...