I have reminded muslims that Jesus is a prophet and asked if in islam are prophets liars. The argument they offer is of course "NO prophets are not liars", but the Christian Bible is corrupted and can't be trusted. Actually this opens a great discussion about why Christians know the Scriptures are the inerrant word of God.
Oh, I know. I have had (seemingly) productive conversations with Muslims. My post was a little tongue-in-cheek as far as a strategy... but accurate in its description.