[cflsystems]

Ok answering my own question

This Smarty3 upgrade works on 4.5.0 but:
1. some files are missing in 4.5.0 so their upgrade has to be deleted from the diff file.
2. the upgrade does not have the 2 new skins (since they are new for 4.5.0) so their templates have to be patch manually based on skin/common_files changes in the diff file
3. not sure about 4.4.5 but on 4.5.0 there were like 6 files to be patched manually


There are files missing from the upgrade diff file that needs to be patched on 4.4.5 and 4.5.0 as well. QT has not checked everything so in some cases there will be errors and site will not load. This is what I found so far but there could be more missing files

1. cleanup.php is not included in the diff file but it needs to be patched as well. New code

$result = $smarty->clearCache(null);
$result = $smarty->clearCompiledTemplate();

2. function.math.php is not included in the diff file but needs to be patched as well. New code

$error_prefix = 'math ``<b>'.htmlspecialchars($params['equation']).'</b>\'\' in ``'.$smarty->template_resource.'\'\': ';

3. configuration.php is not included in the diff file but need to be patched as well. New code

          if 
(func_option_is_changed($option, $v)) 
{
$smarty->clearCompiledTemplate();
$smarty->clearCache(null);
break;
}

So anyone looking to upgrade smarty - wait. The provided upgrade is buggy