My searching has not pulled up anything definitive either way.
If your searching had included the source document (JAR-FCL 1), you would have found JAR-FCL 1.155(b)(1), which states:
Experience. An applicant for a CPL(A) who is not a graduate from an integrated flying training course shall have completed as a pilot on aeroplanes having a certificate of airworthiness issued or accepted by a JAA Member State at least 200 hours of flight time.
A quick call to the licensing authority of the relevant JAA state would then have confirmed that an FAA C of A is acceptable.