system(), passthru(), exec() not working as from command line

I'm trying to get gnupg (OpenPGP) working on my system, which is Solaris 2.6 on Sparc, with PHP 4.0.6 and Apache/Stronghold. I have the program compiled, as it works at the command line. Here's what works at the command line: /usr/local/bin/gpg --encrypt -ao /usr/local/www/htdocs/777/crypted -r '<phplist@newmediaone.net>' /usr/local/etc/www/htdocs/777/plain_text_mesage.txt If I type the above at the command line, when logged in as the user Apache and PHP is running as (nobody), it encrypts the contents of the file /usr/local/etc/www/htdocs/777/plain_text_mesage.txt and writes it to the file /usr/local/www/htdocs/777/crypted, which is what I want. (The directory /usr/local/www/htdocs/777/ is "chmod 777", and PHP can write a file in that directory.) I've tried everything I can think of, but it looks like a command from PHP is not working like it is at the command line. I've tried: system("/usr/local/bin/gpg --encrypt -ao /usr/local/www/htdocs/777/crypted -r '<phplist@newmediaone.net>' /usr/local/etc/www/htdocs/777/plain_text_mesage.txt"); passthru("/usr/local/bin/gpg --encrypt -ao /usr/local/www/htdocs/777/crypted -r '<phplist@newmediaone.net>' /usr/local/etc/www/htdocs/777/plain_text_mesage.txt"); exec("/usr/local/bin/gpg --encrypt -ao /usr/local/www/htdocs/777/crypted -r '<phplist@newmediaone.net>' /usr/local/etc/www/htdocs/777/plain_text_mesage.txt"); $command= `(/usr/local/bin/gpg --encrypt -ao /usr/local/www/htdocs/777/crypted -r '<phplist@newmediaone.net>' /usr/local/etc/www/htdocs/777/plain_text_mesage.txt`; (Each of the above 4 lines of code probably word wrapped in this email, and the last line contains backtics, not single quotes.) So, I'm stumped. I was following the basics of the article at: http://hotwired.lycos.com/webmonkey/00/20/index3a.html?tw=programming Thanks, Peter Janett New Media One Web Services ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ New Upgrades Are Now Live!!! Windows 2000 accounts - Cold Fusion 5.0 and Imail 7.1 Sun Solaris (UNIX) accounts - PHP 4.0.6, mod_perl/1.25, Stronghold/3.0 (Apache/1.3.22), MySQL 3.23.43 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PostgreSQL coming soon! http://www.newmediaone.net webmaster@newmediaone.net (303)828-9882