Plesk / PHP -- FAILED OPENING REQUIRED

[TayR]

I am trying to copy my website files from my local computer to my production server which is on CentOS 5 and Plesk 10. The files have been copied but when i navigate to the home page there is a error log entry:

PHP Fatal error: require() [<a href='function.require'>function.require</a>]: Failed opening required '/var/www/vhosts/crosis.com/httpdocs/frameworks/codeigniter//var/www/vhosts/crosis.com/httpdocs/config/constants.php' (include_path='.:') in /var/www/vhosts/crosis.com/httpdocs/frameworks/codeigniter/codeigniter/CodeIgniter.php on line 52

I tried to did deepr and discovered the php command "is_dir" isnt working correctly. When i use it to tell me if this is a directory: "/var/www/vhosts/crosis.com/httpdocs" it returns TRUE. However when i inspect deeper into that directory: "/var/www/vhosts/crosis.com/httpdocs/frameworks" it returns FALSE. Yes frameworks is a directory but php is indicating it is not!\

Permissions on frameworks: rwx r-x r-x . Group: psacln

Any ideas on how to fix this? I notice plesk 10 is using PHP version 5.1.6 where as my local pc was using PHP v 5.3.1. Does this make a difference?

thanks