I have re-written the PHP 5.3.8 function for quoted_printable_encode into PHP for use with PHP < 5.3. Tested with PHP 5.2.11.
<?php
define('PHP_QPRINT_MAXL', 75);
function php_quot_print_encode($str)
{
$lp = 0;
$ret = '';
$hex = "0123456789ABCDEF";
$length = strlen($str);
$str_index = 0;
while ($length--) {
if ((($c = $str[$str_index++]) == "\015") && ($str[$str_index] == "\012") && $length > 0) {
$ret .= "\015";
$ret .= $str[$str_index++];
$length--;
$lp = 0;
} else {
if (ctype_cntrl($c)
|| (ord($c) == 0x7f)
|| (ord($c) & 0x80)
|| ($c == '=')
|| (($c == ' ') && ($str[$str_index] == "\015")))
{
if (($lp += 3) > PHP_QPRINT_MAXL)
{
$ret .= '=';
$ret .= "\015";
$ret .= "\012";
$lp = 3;
}
$ret .= '=';
$ret .= $hex[ord($c) >> 4];
$ret .= $hex[ord($c) & 0xf];
}
else
{
if ((++$lp) > PHP_QPRINT_MAXL)
{
$ret .= '=';
$ret .= "\015";
$ret .= "\012";
$lp = 1;
}
$ret .= $c;
}
}
}
return $ret;
}
?>
