by Patrick Pollet.
Ok I guess I found it. Some of the fields in table mdl_course have been deleted in Moodle 2.4.3 such as 'numsections' and this break operation get_my_courses ; you could see it by looking at file wspp_db_errors.log located in your moodledata directory that should contains a dump of some database execptions
A quick fix is to edit function get_my_courses in wspp/server.class.php at line 982
change
$res = ws_get_my_courses($uid, $sort, $extrafields);
to (remove extra parameter named $extrafields)
$res = ws_get_my_courses($uid, $sort);
Next week, when in my office, I shall push on github a cleaner fix to this and other small details I noticed when trying to fix this
Cheers