[Webdev] php3 -> 4 incompatability?

[Matthew Sammon]

OK I have 2 accounts on the same web host.  However they are running
slightly different versions of Apache/PHP.

Account 1 is:
	Apache/1.3.6 (Unix) PHP/3.0.16
	mod_perl/1.21 mod_ssl/2.2.8 OpenSSL/0.9.2b
Account 2 is:
	Apache/1.3.6 (Unix)
	ApacheJServ/1.1 PHP/4.0.1pl2 mod_perl/1.21 mod_ssl/2.2.8
	OpenSSL/0.9.2b

On account 1 the following prints out useful info:
echo $SCRIPT_FILENAME . "<BR>\n";
echo $SERVER_SOFTWARE . "<BR>\n";
echo $PHP_SELF . "<BR>\n";

On account 2: Nothing.

Why is the account running PHP4 not able to use Apache and PHP
predefined variables?

The reason I need to have (at the very least) $SCRIPT_FILENAME
available is that it's used in all my scripts.  Doh!

Thanks

-- 
Matthew Sammon <sammonm at tcd.ie>.  CmpSci3, TCD.