I've noticed a difference in how (! $a == $b) and ($a != $b) behaves between in PHP 4.04pl1.  I think those should be syntactically equivalent, but with PHP 4.04pl1 they are not, whereas with older versions they are.  Here is a script to test this:

<?
$a = "foo";
$b = "bar";

echo "\nTest 1: ";
echo (! $a == $b) ? "true" : "false";

echo "\nTest 2: ";
echo ($a != $b) ? "true" : "false";

echo "\n";
?>

With PHP4.04pl1 the results are:

Test 1: false
Test 2: true

With PHP3.18 the results are:

Test 1: true
Test 2: true

It would seem that the results with PHP 4 are wrong here, please advise.  Information about my system follows:

OS: Redhat Linux
Kernel: 2.4.1
PHP Version: 4.04pl1
'./configure' '--disable-debug' '--with-config-file-path=/usr/local/etc' '--enable-bcmath' '--with-mysql' '--with-pgsql' '--with-gdbm' '--with-openssl' '--with-curl' '--with-readline' '--enable-inline-optimization'

PHP Version: 3.18
./configure '--disable-debug' '--enable-force-cgi-redirect' '--enable-track-vars' '--with-config-file-path=/etc/httpd/conf' '--enable-sysvsem' '--enable-sysvshm' '--with-mysql'

I am using the standard php ini files (php.ini-dist and php3.ini-dist) with no changes in both tests.  Please advise.