Joomdle system check / incorrect joomla url ?!?

Hi all,
Just discovering this amazing component ! Thx Antonio for that great work !
Even if i get joomla (3.4) and moodle (2.6) connected (course list is showing), i still got "a red cross in system checks" :
Joomdle webservice : "Joomla url seems to be misconfigured"
=> Btw, in moodle, i put the correct url (subdomain) so can't figure out where is the problem :'(
May be you have an idea ?
Last info : moodle and joomla are not in the same domain
Thx for all.

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