JAR-FCL 1.005(a)(2) states:
"Whenever licences, ratings, authorisations, approvals or certificates are mentioned in JAR–FCL, these are meant to be licences, ratings, authorisations, approvals or certificates issued in accordance with JAR–FCL. In all other cases these documents are specified as e.g. ICAO or national licences."
Appendix 1 to JAR–FCL 1.160 & 1.165(a)(4) states
"Applicants holding a valid IR(A) shall be fully credited towards the dual instrument instruction time."
Since this latter does not refer specifically to an ICAO or national IR, it means one issued in accordance with JAR-FCL. An FAA IR, therefore, does not count.