Fatal error: Undefined class name

[dandowftm]

help, i am trying to install roundcube and have encountered an error. so far i have created my database, uploaded the files and now when i go to run the installer i get the following error,

Fatal error: Undefined class name 'rcubemail_install' in /home/dandow/public_html/installer/index.php on line 55

any help on this matter would be greatly appreciated

thanks in advance guys!