Same problem has happened to me.
Only I was getting the error for docman component and rsitems 1.4.2 alpha module, when using together.
Solution founded in file administrator/components/com_docman/contrib/pear/HTML_Select.php file.
Just delete 3 lines in file:
//only load if it hasn't already been loaded
if(!class_exists( "PEAR")) {
require_once dirname(__FILE__) . '/PEAR.php';
}
require_once dirname(__FILE__) . '/HTML_Common.php';
New code:
//only load if it hasn't already been loaded
require_once dirname(__FILE__) . '/HTML_Common.php';
It works, without a problems.
But it only works with rsgallery2_1.13.2-alpha.
With new version of gallery, even [SVN] the docman and rsitems 1.4.2 alpha module would not work at all.
Cheers
