Sometimes no elements are populated except x.start.time

Hi,

We have a transient issue with SCORM 1.2 and Moodle 2.x. On some occasions, but not always, in the DB, table xxx_scorm_scoes_track, the only element that is stored for the attempt is x.start.time. The effects of this inconsistency are the following:
 
1. When the user returns to the activity, nothing is stored anymore
2. When the user creates a new attempt, this is allowed, but only data pertinent to that new attempt are stored (the attempt records are overwritten)
 
We also tried to "repair" the DB by eliminating attempts with too few elements stored, but this does not solve properly the problem, especially when there were created another attempt.
 
Anyway, the root cause is that originally no elements were stored except x.start.time. Apparently, the problem is on the client side (JavaScript). We tried to track down outgoing requests via tcpdump and have found that sometimes they are silently lost on the client side instead of being sent to the server. Apparently, the issue is more probable to occur having bad network connection.
 
The issue applies to any kind of course generated by Articulate as well as to custom-made material produced by using a SCORM wrapper.

Our server platform is Centos 5.6 with PHP 5.2.x and MySQL 5.0.

 
Can anyone help us out please?