设置虚拟主机出问题(NameVirtualHost *:0 has no VirtualHosts)

NameVirtualHost *
<VirtualHost *>
ServerAdmin webmaster@localhost
ServerName mall.zjjkgl.cn
DocumentRoot /home/gjx/public_html/system/software
<Directory />
Options FollowSymLinks
AllowOverride None
</Directory>
<Directory /home/gjx/public_html/system/software>
Options FollowSymLinks MultiViews
AllowOverride None
Order allow,deny
allow from all
# Uncomment this directive is you want to see apache2's
# default start page (in /apache2-default) when you go to /
#RedirectMatch ^/$ /apache2-default/
</Directory>

ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/
<Directory "/usr/lib/cgi-bin">
AllowOverride None
Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
Order allow,deny
Allow from all
</Directory>

ErrorLog /var/log/apache2/error.log
</VirtualHost>

NameVirtualHost * 这里怎么不写端口呢?
NameVirtualHost *:80