Malwarebytes shows AutoIt as a trojan

Hi,

Today after updating the Malwarebytes database, the Malwarebytes scan showed being executed AutoIt3.exe as trojan, and deleted it at the system reboot:

Malwarebytes Anti-Malware 1.75.0.1300
www.malwarebytes.org

Version de la base de données: v2013.05.31.06

Windows 7 Service Pack 1 x64 NTFS
Internet Explorer 10.0.9200.16576

..........

Processus mémoire détecté(s): 1
C:\Program Files (x86)\AutoIt3\AutoIt3.exe (Trojan.Inject.AI) -> 820 -> Suppression au redémarrage.

This makes me very anxoius. Have I installed a Trojan with this marvelous package? Is there any virus, which attacks AutoIt3.exe ?

Is there any possibility to check, if really this program is/is not a trojan? Is there any signature, which allows to control if the .exe is not altered?
Only 32 bits version seems to be considered as trojan.

Any comment and help will be welcomed, as I am a bit anxious because of this detection.

Best regards

User3D