In my account, it doesn't matter which version I choose, they all have --disable-fileinfo set in the configuration. Here is the relevant section from my phpinfo():

'./configure' '--build=x86_64-redhat-linux-gnu' '--host=x86_64-redhat-linux-gnu' '--target=x86_64-redhat-linux-gnu' '--program-prefix=' '--prefix=/opt/php55' '--exec-prefix=/opt/php55' '--bindir=/opt/php55/bin' '--sbindir=/opt/php55/sbin' '--sysconfdir=/etc' '--datadir=/opt/php55/share' '--includedir=/opt/php55/include' '--libdir=/opt/php55/lib64' '--libexecdir=/opt/php55/libexec' '--localstatedir=/var' '--sharedstatedir=/opt/php55/com' '--mandir=/usr/share/man' '--infodir=/usr/share/info' '--with-libdir=lib64' '--libdir=/opt/php55/lib/php' '--with-sqlite3=shared,/opt/sqlite3' '--with-pdo-sqlite=shared,/opt/sqlite3' '--disable-fileinfo' '--enable-cli' '--enable-bcmath' '--enable-calendar' '--enable-dbase' '--enable-exif' '--enable-ftp' '--enable-gd-native-ttf' '--enable-libxml=static' '--enable-magic-quotes' '--enable-mbstring' '--enable-pdo=static' '--enable-soap' '--enable-sockets' '--enable-sqlite-utf8' '--enable-zend-multibyte' '--enable-zip' '--enable-intl' '--with-icu-dir=/opt/icu-last' '--with-bz2' '--with-curl' '--with-curlwrappers' '--with-freetype-dir=/usr' '--with-gd' '--with-gettext' '--with-imap' '--with-imap-ssl' '--with-jpeg-dir=/usr' '--with-kerberos' '--with-libexpat-dir=/usr' '--with-mcrypt' '--with-mhash' '--with-mime-magic' '--with-mm' '--with-mysql=mysqlnd' '--with-mysql-sock=/var/lib/mysql/mysql.sock' '--with-mysqli=mysqlnd' '--with-openssl' '--with-openssl-dir=/usr' '--with-pcre-regex' '--with-pdo-mysql=mysqlnd' '--with-pdo-pgsql=/usr/pgsql-9.3' '--with-pgsql=/usr/pgsql-9.3' '--with-pic' '--with-png-dir=/usr' '--with-pspell' '--with-tidy' '--with-ttf' '--with-xmlrpc' '--with-xpm-dir=/usr' '--with-xsl' '--with-zlib' '--with-zlib-dir=/usr'

Hello jchandler,

You may want to check in with our Live Support team for your server's individual specs. I was told that it was included, but there may be an issue either on your server or with your particular account that they can address.

Kindest Regards,
Scott M

According to the Live Support Team: "It is not possible to set it on this server. It is a very resource intensive extension, and is disabled by the server configuration."