narrowed the problem down further, Its directly related to me trying to extend the mysqli class. If I take out the extend it closes properly, If I put in the extend with no functions at all it does not close properly

So
<?
$mysqli = new extend_mysqli('localhost','billing','billing','billing');
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}
?>
Connection does not close properly
<?
$mysqli = new mysqli('localhost','billing','billing','billing');
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}
?>
Connection does close properly.

My C more then sucks so excuse me for even trying..

in mysqli.c intern->zo.ce = class_type;

intern->zo.ce is only used 4 places in mysqli.c
1. When you assign it
2. stmt and result entrys, not changed my extending the class
3. line 135, when closing the object, In this same statement you also run mysql_close.

This if statement is returning false because
intern->zo.ce == mysqli_link_class_entry is wrong, by extending the class I have changed the class type therefore breaking the closing of the object.

I hope this helps fix the problem

No your analysis looks correct.
Try the following patch:
diff -u -p -d -r1.41 mysqli.c
--- ext/mysqli/mysqli.c 23 Jun 2004 16:47:25 -0000      1.41
+++ ext/mysqli/mysqli.c 5 Jul 2004 18:48:51 -0000
@@ -132,7 +132,7 @@ static void mysqli_objects_free_storage(
        FREE_HASHTABLE(intern->zo.properties);

        /* link object */
-       if (intern->zo.ce == mysqli_link_class_entry) {
+       if (instanceof_function(intern->zo.ce, mysqli_link_class_entry TSRMLS_CC)) {
                if (my_res && my_res->ptr) {
                        MY_MYSQL *mysql = (MY_MYSQL *)my_res->ptr;

Thanks, maybe I should pull out some C books and try to help out more...

Anyway that patch worked, sprinkle some pixie dust on it or what ever you do and send it on its way.

Not the right place for this but thought I would mention it so you could pass it on.

If class_type changes when you extend then using that in a class at all might cause a problem??

Did a quick scan and found the following extensions use class_type.

xsl
spl
sqlite
dom
simplexml
mysqli

This bug has been fixed in CVS.

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