Mel Gibson and Jay Leno

Mel Gibson took responsibility for the end of his 28-year marriage and happily confirmed his girlfriend is expecting his eighth child: "I guess I'm Octo-Mel."

Gibson was the first of several special guests stopping by this week to celebrate the last week of Jay Leno's 17-year run at the Tonight Show.

Leno also asked about reports that Gibson's 39-year-old Oksana Grigorieva girlfriend is pregnant. "This is true. We're gonna have a child," Gibson said. He also talked about the end of his marriage to wife Robyn Gibson.

"Look. When it's all said and done, I did a pretty good hatchet job on my marriage myself," Gibson said. "I'm to blame. If you're inclined to judge, put it here."

He also said the couple's split doesn't affect his feelings toward Robyn. "My wife and I, our marriage ended three years ago and we've been separated ever since then," Gibson said. "These things happen. It's unfortunate, it's sad, but you know she is an admirable woman — we still got kids together. We're friends."

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