1. Create new menu root for example *merchant*

2. Override function hook_preprocess_page(&$vars) in templete.php and add the following code:

global $user;
if (in_array(‘Merchant’, $user->roles)) {
$vars['nav_links'] = menu_navigation_links(“menu-merchant”);
} elseif (in_array(‘…’, $user->roles)) {

}

3. Add the following code in your tpl file:

<?php print theme(‘links’, $nav_links) ?>

That is all.

Also see:

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