This CodeLet alter the 'uc_paypal_wps_email' variable when PayPal payment is enabled with Ubercart & sets to node author's PayPal account email address. This requires creating a field on user's account with name 'PayPal Email' (field_paypal_email).

CodeLet
<?php/** * @file *  * @author DrupalD  *//** * Implementation of hook_form_alter *  * @param unknown $form * @param unknown $form_state * @param unknown $form_id * @author DrupalD */function mymodule_tweaks_form_alter(&$form, &$form_state, $form_id) {    if ($form_id == 'uc_paypal_wps_form') {        $am__cart = array_values(uc_cart_get_contents());        $sn__uid = $am__cart[0]->uid;        $am__paypal = db_select('field_data_field_paypal_email', 'ppe')                    ->fields('ppe', array('field_paypal_email_email'))                    ->condition('entity_id', $sn__uid, '=')                    ->execute()                    ->fetchAssoc();        $form['business']['#value'] = $am__paypal['field_paypal_email_email'];        //When testing paypal  as buyer. DO NOT REMOVE comments unless you are testing paypal.//         $form['email']['#value']  .= '-buyer';     }}?>
Info file details
name = Ubercart Tweaks
description = Ubercart Tweaks. Built by <a href="http://bit.ly/1N7nWf0">Drupal Developer</a>.
dependencies[] = uc_paypal
package = DrupalD
core = 7.x
DrupalD
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