I entered Doha with the two Israeli entrance and exit ticket stapling at the back (I forgot to remove them). No question asked at all. However, I did come into a bit of problem as they were unhappy that I entered Doha with another passport before. I was told that I could only use Canadian passport from now on or else I might be sent back. Called the embassy when I got home asking if there is such policy, I got a rather vague answer