Odd issue during online site deployment

Hi all
i'm having an odd issues after installing and setting Block theme in my shared host but this
issue doesn't affect my same localhost configuration
Using Drupal core 7.10 + Block Theme 7.x-1.0
When i go to structure->blocks->add block, this warning message appears:
Notice: Undefined offset: 1 in blocktheme_get_blockthemes() (line 256 of /home/mhd-01/www.cloudjournal.it/htdocs/sites/all/modules/blocktheme/blocktheme.module).

It happens only in the online deployment , not in localhost !

What could be the problem??

Thanks to all