need to replace default drupal user picture with an image field from user profile Need to replace the user_picture with my own field_profile_picture(since i've provided a nice crop with imagefield crop). 

I've succeeded in getting the file path using template_preprocess_user_picture and the code

 function theme_preprocess_user_picture(&amp;$variables) {        
    $account = user_load($variables['account']-&gt;uid);
    if(isset($account-&gt;field_profile_picture['und'][0]['uri'])) {
        $variables['user_picture'] = $account-&gt;field_profile_picture['und'][0]['uri'];


the user_picture is getting replaced by the file path.... how to render the image???

Anyone Please....
how to render the image???


Sounds like you're probably looking for image_style_url(). Assuming you have an image preset called thumbnail, try something like this:

$picture_style = 'thumbnail';
$picture_uri = $account-&gt;field_profile_picture['und'][0]['uri'];
$variables['user_picture'] = image_style_url($picture_style, $picture_uri);