Arnold Schwarzenegger's known for his gun-toting characters ... but it was actually a benign watch that caused him problems at an airport Wednesday -- and the aftermath was a freaking mess.
The actor-turned-politician was held at the Munich Airport on Wednesday after trying to take an "unregistered" luxury watch through customs ... the Terminator didn't try to fight his way out of this one ... instead being spotted calmly hanging with customs agents.
