See http://moodle.org/mod/forum/discuss.php?d=181931 for the long story.

Shortly: sometimes there are situations in which ORIG_PATH_INFO env variable plays the role of the missing PATH_INFO: among them some shared server offerings from Hosting Companies like 1&1. This kind of setup will prevent Moodle to correctly provide raw assets using slash arguments, especially when it is warmly recommended like for the AICC/SCORM activity.

The patch proposal in http://moodle.org/mod/forum/discuss.php?d=181931#p792671 gives the opportunity to mask the limitations of such a server environment. This proposal could be evaluated in terms of correctness&regression and of the other parts of the core code in which ORIG_PATH_INFO is taken into account (e.g. external libraries) or where PATH_INFO is straight used.

For the sake of simplicity, the patch proposal focuses to the main blocking issue, the inability of serving files of a AICC/SCORM package and nothing more.