[Plugin: Get the Image] Error in installation

Hi, i receive this error when i try to install this plugin:

Fatal error: Cannot redeclare get_the_image() (previously declared in http://mydomain.ext/wp-content/themes/ego/includes/get-the-image.php:55) http://mydomain.ext/wp-content/plugins/get-the-image/get-the-image.php on line 188

What i can do?
I use wp 3.3.1 and last version of plugin

Thanks.

http://wordpress.org/extend/plugins/get-the-image/