This bug happens when requesting a lot (1000+) rows from an MSSQL database 
or less lines if you've executed a bunch of other code first.  My test case 
was with a table called "data" with three fields: 

     "pt_index(int)","pt_time(datetime)","pt_data(real)"
 
I set the index to 22 for each row, pt_time to each minute of the day, and
pt_data to random values.  My code was working fine under 4.0.5, but with 
4.1.0 and 4.1.1 it generates an application error in php.exe - trying to 
reference a null pointer.  Interestingly, it works fine if I didn't supply
the date ranges.  Anyways, I searched through the code and saw I was 
getting the exception in the memory allocation function which means the 
heap is being corrupted somewhere else.  Any ideas on what was added?  

<?php
$link = mssql_connect ("127.0.0.1","","") or die (mssql_get_last_message());
mssql_select_db("TestDB");

$req = "select * from data where pt_index=22 and ".
	"pt_time >= '2001-12-3' and pt_time < '2001-12-4'";

$data=mssql_query($req, $link) or die (mssql_get_last_message());

while ($row=mssql_fetch_array($data)){
	print_r($row);
	echo "<br>";
}
?>