donate button in a custom block doesn't work

I had to hack directly into the lm_paypal_donations.module:

	$content .= '******* è un progetto open-source e no-profit. Ogni contributo è re-investito nel progetto.' . //missione
	lm_paypal_donate(array(10,array(20),30,50,100,200,300), 'EUR', 'donazione a *******', '', ''). '<br>';//tasto Invia Donazione

because the following code makes an unresponsive paypal button:

<?php
if (function_exists('lm_paypal_donate')) {
  // 10 = amount, 'USD' is the currency followed by a description
  print 'We would really like a $10 donation ' .
    lm_paypal_donate(10, 'USD', 'donation to example.com') .'<br/>';
  // The amount is a one element array so an text input with the one value as
  //  default
  print 'Write your own amount to give, we suggest $5' .
    lm_paypal_donate(array(5), 'USD', 'donation to example.com') . '<br/>';
  // The amount is a multi element array so a select will be used. Note if one
  //   of the elements is itself an array that will be the default selection
  // The final two parameters are an alternative button (here we use the default)
  //   and a replacement label before the amount
  print 'We would really like a $10, or more, donation ' .
    lm_paypal_donate(array(5,array(10),15), 'USD', 'donation to example.com', '', 'Donation') .'<br/>';
}
?>