<?php
$URL="http://dl.panticz.de/magento/contact_attachment/form.phtml.diff";

echo "wget -q $URL -O - | patch -p2 \

/var/www/app/design/frontend/default/default/template/contacts/form.phtml";

echo "<div><pre>";
</pre></div>

$c = curl_init();
curl_setopt($c, CURLOPT_URL, $URL);
curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);

echo htmlspecialchars(curl_exec($c));

curl_close($c);

echo "";

?>

<?php
$URL="http://dl.panticz.de/magento/contact_attachment/IndexController.php.diff";

echo "wget -q $URL -O - | patch -p2 \

/var/www/app/code/core/Mage/Contacts/controllers/IndexController.php";

echo "<div><pre>";
</pre></div>

$c = curl_init();
curl_setopt($c, CURLOPT_URL, $URL);
curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);

echo htmlspecialchars(curl_exec($c));

curl_close($c);

echo "";

?>

<?php
$URL="http://dl.panticz.de/magento/contact_attachment/Mage_Contacts.csv.diff";

echo "wget -q $URL -O - | patch -p2 \

/var/www/app/locale/de_DE/Mage_Contacts.csv";

echo "<div><pre>";
</pre></div>

$c = curl_init();
curl_setopt($c, CURLOPT_URL, $URL);
curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);

echo htmlspecialchars(curl_exec($c));

curl_close($c);

echo "";

?>

Links
http://www.blog.magepsycho.com/adding-upload-field-in-contact-form-and-send-as-attachment/
http://www.magentocommerce.com/boards/viewthread/440759/