The legislation apparently has loopholes written to facilitate Canadian interoperability with those who still use cluster bombs (the US). The two key holes* are: Canadian commanders ordering personnel from non-signatory countries to use them and secondment issues.
* The other exceptions reflect other issues. Investment in companies that make cluster bombs is almost certainly not an issue raised by DND but by other folks in the government. Transit through Canadian territory is probably something that DND does care about--that American planes overfly Canada all the time, and Canada is not interesting in telling the Americans to fly around Canada when CBs are on board.
Regarding the former: when Canadian commanders go into the field, they take with them a letter of intent from above them in the chain of command (CEFCOM until the new institution kicks into gear, Deputy Chief of Defence before CEFCOM existed). This letter tells the commander going into the field what he/she can and cannot do. I gained via Access of Information request (akin to Freedom of Information request) several of these letters. The earlier ones made it clear that Canadians could not use landmines or ask contingents from other countries working under them to deploy landmines. The more recent ones use very similar language about cluster bombs--that Canadian officers could not ask other countries to use cluster bombs for them. So, the reality is that the CF is already abiding by the treaty even before it becomes ratified. While these letters can be revised or changed by another order, this is unlikely given that these letters are vetted/written in part by the military's lawyers.
It is not clear why the Conservative government is providing a loophole that the military is unlikely to ever use. The disgruntled Foreign Affairs personnel blames a split between Foreign Affairs and DND, but I am confused as to whether and why the CF would want an exception about condoning the use by others given past behavior.
Regarding the latter: when Canada sends its personnel to work in another country's military, it is hard but not impossible to impose upon them restrictions such as no cluster bomb use. The idea of these "secondments" is for the officers to be treated as one of the receiving country's personnel so that they can learn how that country operates and can fulfill the functions of the billet (the position) they serve. Canada lost heaps of cred when it pulled its personnel out of British ships during the Falklands War as the Brits then had to find personnel from elsewhere to staff these positions. The seconded officers are not just sitting around watching but filling real jobs. So, putting limitations on them that would make them not as useful as the regular officers cuts into the program of military exchanges.
However, it is not impossible. When I was at the fighter base in Bagotville in June of 2011, I bumped into a British fighter pilot who had served with the Canadians in the skies over Libya. In our short conversation, it became clear that his rules were not identical to the Canadian ones and that British officers were keeping an eye on him to help him finesse the differences.
Still, I do understand why the CF and DND would want a secondment exception. In my humble opinion, I do not think this is such a travesty.
What all this demonstrates really are two things: the intent of the CF to respect international law; and the ignorance that the civilians seem to have about the Canadian military. It is not clear why the Conservatives felt a need to carve out such exceptions especially since the US works with plenty of countries that have restrictions inspired by the cluster bomb treaty and that are pretty similar if not identical to those produced by the landmine treaty.
Oh, and a third thing: it would have been nice if the author of this article had talked to someone familiar with the CF, rather than just human rights advocates and one government spokesman. How about interviewing a Judge Advocate General type (a military lawyer)? Why not take a look at the orders given to the commanders in the field? The way Access of Information requests work is once they give documents to the person requesting them, the docs are made public. So, my asking for letters of intent given to Canadian commanders over the past ten years (I have several but not all, and they are at work, not at home) means that any journalist could find these docs if they looked for them.
Of course, I am not an expert on international law, but then again, it would have been swell if the writer had consulted one.