My best understanding of Italian law (based on correspondence with a native and a guide I found on European knife laws) is that you cannot carry any knife on your person. There are exceptions for specific purposes of carry such as gardening tools or work tools, but "EDC" for all intents and purposes is prohibited. Daggers are apparently outright illegal even to own without permit.
I am told that carry of obvious non-weapon knives inside enclosed containers is legal, such as eating utensils inside a food container or picnic basket. I personally brought a Gerber multitool with me back in '97 (even brought in on the plane with me as this was pre-9/11) but kept it in my suitcase in my room, or in a backpack deep down at the bottom so it would be apparent there is no intent for use as a weapon. Overall I found Italian law enforcement to be rather friendly blokes, and not the suspicious or over-aggressive type, and so I never had encounters beyond asking directions.
If you buy there, I recommend mailing it home just as a precaution, though checked luggage should be fine coming back to the US so long as it's not an automatic or ballistic knife. US Customs has no other restrictions on cutlery beyond those and the law has even been reinforced on that front recently by that new bill that passed
