Been there, done that, frenchy.
Had to go to Poland for work, took out all the pointy stuff and gadgets from my briefcase. I knew I would possible need my leatherman whan I got to site so it went in the hold.... on the way out.
Got to site, needed the tool, got it out did the job and put the tool in my briefcase. Next went to airport, with briefcase. Went through the first security check in Krakow no problem, went on to Warsaw for the next leg of my journey when they found the leatherman. I was asked to one side by some very large gentlemen with even bigger guns. At that point I didn't understand why I was being taken to one side until I remembered the leatherman, OMG, that's it 3 yrs Polish prison. I confessed I'd forgotten it was there. I explained what it's use was for, for me it was lost and I was sure they were going to confiscate it or worse to me.....idiot.
The next thing I know the tool is put in a security pouch and I'm been frog marched to the door of the aircraft with 3 armed guards and escorted to my seat, having walked past everyone else. The pouch was given to the aircrew. I got to Paris and the aircrew gave me back the tool as I was leaving the aircraft.
My only regret was I didn't pick up a Lotto ticket that day. Someone was smiling on me.