While setting up a premium WordPress Theme and customzing this WordPress theme to client’s requirements, I got the following errors in the footer code. The theme author had used a php function which was not part of the theme files.
Fatal error: Call to undefined function: twitter_messages()
Reason for the error is that you need to add and activate Twitter for WordPress Plugin. Twitter for WordPress displays yours latest tweets in your WordPress blog.
Just go to your WordPress Admin > Plugins > Add New and search for “Twitter for WordPress”. Install and activate. Don’t forget to setup your theme options and provide twitter account name to fetch the data.
Hope that helps.