I found a blog and I followed its instructions and it works! I share the solution Link to Blog
I put these lines in /etc/make.conf:
USE="apache2 mysql php pam ssl xml xml2 berkdb innodb jpeg png"
phpmyadmin, unicode pcre:
USE="apache2 mysql php pam ssl xml xml2 berkdb innodb jpeg png pcre session unicode"
/etc/init.d/apache2, public_html ( ~), -D USERDIR:
APACHE2_OPTS="-D DEFAULT_VHOST -D PHP5 -D USERDIR
mysql ( ) mysql, , :
/usr/bin/mysql_install_db