Fatal error: can't pass function output by reference

In PHP 5.05 you can't pass a function's output by reference.

Theme editor calls file_check_directory() (defined in 'includes/file.inc') with the output of file_create_path passed by reference as the first argument.

The fix requires modifying line 519 of 'modules/theme_editor/theme_editor.module from:

if (!file_check_directory(file_create_path(variable_get('theme_editor_path', 'theme_editor')), FILE_CREATE_DIRECTORY)) {

to:

if (!file_check_directory($tmp = file_create_path(variable_get('theme_editor_path', 'theme_editor')), FILE_CREATE_DIRECTORY)) {