[Solve] "The mcrypt extension is missing. Please check your PHP configuration" Phpmyadmin Error in Ubuntu 13.10

I've done installation phpmyadmin on Ubuntu 13.10 with apache web server. I restarted apache2 and after login to phpmyadmin, on the bottom of the page show this error: "The mcrypt extension is missing. Please check your PHP configuration." like screenshot below:

So, how to fix this problem?

It's bug is missing mcrypt.ini, where the file located in /etc/php5/conf.d/, which should be in /etc/php5/mods-available/. So we should move mcrypt.ini into /etc/php5/mods-available/ with the following commands below:

1. Run the Terminal, and switch to superuser / root by type: sudo su
2. Then move mcrypt.ini file into /etc/php5/mods-available/ |

mv -i /etc/php5/conf.d/mcrypt.ini /etc/php5/mods-available/

3. Then type this command:
   

   php5enmod mcrypt

4. Then restart apache2:
   

   service apache2 restart

So, you will not find error on the bottom of the phpmyadmin page.