I have the same problem as that described in bug # 7503.
I use cgi PHP with Netscape E.S. 3.51 on AIX 4.3.2.
I always obtain line "#!/lusr/local/bin/php" at the beginning of HTML page
produced by PHP.
I was read all the posts relating to this bug and I circumvented
the difficulty like this: I modified the file cgi_main.c by recopying the lines
related to /* #!php support */
in the first 'if' 'if (cgi && !file_handle.handle.fp) {...'
On the other hand, when I test PHP directly under Shell all is well.
I noted that the program does not pass in same the branch of the 'if' according to whether one calls upon it in Shell or cgi.

Ideas?