Hi Frederic Hadjri,
My apologize for replying late.
On CRM side, the preparation work for a duplicate check on email and phone has been already done (notes 1836711 and 1852883 ) by SAP, if your using CRM 7.0 EHP1.
But on the duplicate check tool side (software component BC-EIM-IQM-IC ),it is not possible.There is no additional TREX engine and no replication of data to there as per my knowledge.So I think it is not possible to extend the phone and email search using TREX.
Thanks,
Cheers!!!
Best Regards
Mukesh.L