Here's the exact text of what Jennings said:
One of the people that’s always inspired me is Harry Hay, who started the first ongoing gay rights groups in America. In 1948, he tried to get people to join the Mattachine Society. It took him two years to find one other person who would join. Well, [in] 1993, Harry Hay marched with a million people in Washington, who thought he had a good idea 40 years before. Everybody thought Harry Hay was crazy in 1948, and they knew something about him which he apparently did not—they were right, he was crazy. You are all crazy. We are all crazy. All of us who are thinking this way are crazy, because you know what? Sane people keep the world the same [ty] old way it is now. It’s the people who think, ‘No, I can envision a day when straight people say, “So what if you’re promoting homosexuality?”‘ Or straight kids say, ‘Hey, why don’t you and your boyfriend come over before you go to the prom and try on your tuxes on at my house?’ That if we believe that can happen, we can make it happen. The only thing that will stop us is our lack of faith that we can make it happen. That is our mission from this day forward. To not lose our faith, to not lose our belief that the world can, indeed, be a different place. And think how much can change in one lifetime if in Harry Hay’s one very short life, he saw change from not even one person willing to join him to a million people willing to travel to Washington to join him.“
So... who is Harry Hay?
Well, here is the Wikipedia entery on Harry Hay.
Harry Hay - Wikipedia, the free encyclopedia
It includes THIS little tidbit:
In the early 1980s, Hay joined other early gay rights activists protesting the exclusion of the
North American Man Boy Love Association (NAMBLA) from participation in
LGBT social movements, most noticeably
pride parades–arguably the most visible signs of LGBT culture–on the grounds that such exclusions constituted a betrayal by the gay community.
[33] In 1983, at a
New York University forum, sponsored by an on-campus gay organization, he remarked "[I]f the parents and friends of gays are truly friends of gays, they would know from their gay kids that the relationship with an older man is precisely what thirteen-, fourteen-, and fifteen-year-old kids need more than anything else in the world."
[49] In 1986 Hay was confronted by police when he attempted to march in the Los Angeles pride parade, from which NAMBLA had been banned, with a sign reading "NAMBLA walks with me."
[14][note 5]
So... if Jennings praises Harry Hay and supports Harry Hay, then he is supporting NAMBLA as well.
This is a completely separate issue from what he told the kid at school (which borders on NAMBLA-like support as well).
Once is happinstance. Twice? Twice is personal preference.
Elliot