As I see it, the short answer to this question, posed in Tuesday's Jerusalem Post, is yes. Here is the long answer:
On Passover, which begins Monday night, Jews commemorate the Exodus from Egypt, during which the Israelites were in too much of a rush to let their dough rise and therefore had to pack unleavened bread, by refraining from "leaven" (chometz). In addition to obvious things like bread and cake, this category includes foods that might have ingredients derived from chometz or that might otherwise be contaminated by chometz. The rabbis, in what is known as "building a fence around the Torah" (also known as "making Judaism more of a pain in the ass than it has to be"), extended the prohibition further, decreeing that kitniyot—legumes, seeds, and even certain vegetables that are said to resemble chometz in some way (because they rise when mixed with water, say, or because they can be ground into something like flour)—also should be avoided. The kitniyot ban has never been followed by Sephardic Jews, and it is increasingly questioned by Ashkenazim as well, especially in Israel. But evidently there are enough Israeli pot smokers who observe the kitniyot ban for the headline question to have arisen.
Leaving aside the legitimacy of the kitniyot rule and the arbitrariness of its application, I don't see why it would prohibit possession or consumption of marijuana on Passover. If an edible seed is prohibited because it could be ground into something resembling flour, that doesn't mean the plant that grows from the seed is prohibited. For example, if coriander and mustard seed count as kitniyot (which they supposedly do), that doesn't mean you can't have cilantro or mustard greens on Passover. It should follow, then, that deseeded marijuana is OK even if hemp seeds (and foods made with them) are prohibited.
Still, I like the twist that Israel's marijuana legalization party put on the controversy:
Israel's Green Leaf Party ("Aleh Yarok") said it was not taking any chances. Following an inquiry by the Post, a spokeswoman for the party said the group was sending out an e-mail to members warning them about hemp's possible kashrut problems.
"We are warning our people not to eat anything with hemp products if they follow the practice of kitniyot on Pessah," said party spokeswoman Michelle Levine. "We are considering announcing a ban on everything containing hemp just to be on the safe side. We are going with the rabbis on this. People should remove all cannabis and hemp from their homes."
Levine said one of the party's main arguments for cannabis legalization was biblical references to it.
"We would like to ask people... if it's listed as not kosher 'for Pessah,' [doesn't] that mean it must be kosher the rest of the year?" said Levine.