This year, besides providing support to other groups participating in cross-language Question Answering (QA) tasks, and submitting runs both for the monolingual Italian and the cross-language Italian/English tasks, the ITC-irst participation in the CLEF campaign concentrated on the Answer Validation Exercise (AVE). The participation in the AVE task, with an answer validation module based on textual entailment recognition, is motivated by our objectives of (i) creating a modular framework for an entailment-based approach to QA, and (ii) developing, in compliance with this framework, a stand-alone component for answer validation which implements different approaches to the problem. Keywords Question answering, Recognizing textual entailment, Tree edit distance, Answer validation