For more about this, see:
http://httpd.apache.org/docs/2.2/mod/mod_proxy.html
https://confluence.atlassian.com/display/DOC/Using+Apache+with+virtual+hosts+and+mod_proxy
Here is my configs to pass to my Atlassian JIRA (port 8080) And Atlassian Confluence (port 8090)
JIRA
<VirtualHost *:80>
ServerAdmin bnp@mos-eisley.dk
ServerName jira.mos-eisley.dk
ServerAlias jira
ProxyPass / http://localhost:8080/
ProxyPassReverse / http://localhost:8080/
<Proxy *>
Order Allow,Deny
Allow from all
Deny from none
</Proxy>
</VirtualHost>
Confluence
The "Deny from 80 10.40.62.77" is actually to stop a spammer identified from that IP Address
The ReWrite Url disables hitting the Confluence Dashboard, redirection to /display/public/ directly
<VirtualHost *:80>
ServerAdmin bnp@mos-eisley.dk
ServerName www.mos-eisley.dk
ServerAlias mos-eisley.dk
DocumentRoot /var/www
ErrorDocument 503 /503.html
RewriteEngine On
RewriteRule ^/dashboard.action.* /display/public/ [PT]
ProxyPass / http://localhost:8090/
ProxyPassReverse / http://localhost:8090/
<Proxy *>
Order Allow,Deny
Allow from all
Deny from 80 10.40.62.77
Deny from none
</Proxy>
</VirtualHost>
Proxy passing a subpart
If You want JIRA or Confluence to run under /jira or /docs - often interesting if www.site.dk has SSL enabled - the proxy part can be configured as:
ProxyPass /docs http://localhost:8080/docs
ProxyPassReverse /docs http://localhost:8080/docs
ProxyPass /jira http://localhost:6060/jira
ProxyPassReverse /jira http://localhost:6060/jira