Description:
------------
When I check an isset of a variable that contain text I receive an error ONLY when i check the last+1 char...

NOTE: Working properly on php4.3.6

Reproduce code:
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<?php
$test = "s";
if(isset($test[1]))
	echo "OK";
else
	echo "ERROR";
?>

Expected result:
----------------
It supposed to return "ERROR" because $test[1] is not existing (in real, there is a \0 in C++ but in php, we are not supposed to see it).
(working fine in php4.3.6)

Actual result:
--------------
We currently get "OK"
If we do an isset of $test[2], we get an error...
Obviously, php check the \0