[dxbsgt]

I am displaying a dropdown with product manufacturer list. It displays all the manufaturers list correctly. When i change the index, no effect on my website. It should go to manufacturer page . And also javascript doest show any page error. Please help me. Here is my code.

<select name="manufacture_list1" id="manufacture_list1"{if $onchange} onchange="javascript: self.location='manufacturers.php?manufacturerid='+ this.options[this.selectedIndex].value;"{/if}>
<option value="">{$lng.lbl_please_select_one}</option>
{foreach from=$manufacturers item=m}
<option value="{$m.manufacturerid}"{if $m eq $manufacturers} selected="selected"{/if}>{$m.manufacturer}</option>
{/foreach}
</select>