Where are you connecting? If it's someplace where the local restrictions prevent you from bringing in six bottles of wine in the form of a 4 liter box, there may be problems, as local laws will be enforced at those locations.

You may luck out at YYZ, I can't picture them checking your boarding pass to see where you are going and looking it up in a table to see if it's a more restrictive state or not, but it's something to be aware of just in case.