"We'll lend them our handcuffs and chains," he told E! News at the FiFi Awards last night. "We'll FedEx them!"
The pair—who credits "love and bondage and whips and chains" with keeping their marriage alive for 28 years—has known the Milk actor for years.
"We used to play tennis together," Hoffman said. "What's interesting is he used to come around and sit in front of our house with Tom Cruise and Timothy Hutton when they were first starting out, and they would just stare, waiting for us to come in. We didn't know until they told us. They would do it at night."
Hoffman also has remained in and out of touch with his Rain Man costar.
"I haven't seen him in awhile," he said. "I did see them when [Katie Holmes] opened All My Sons on Broadway, but before that it had been a long time. You don't see people unless you're working with them…especially when you're handcuffed."
When one reporter compared the Hoffman family to the Cruise clan, he laughed.
"They're all trying to catch up to us," he joked. "Warren Beatty is a close second."
The couple attended the Fragrance Foundation's annual awards ceremony because the missus was nominated for her Lisa Hoffman Variations. The 71-year-old actor couldn't have been more proud of his partner.
"Each time she gave birth—four times in eight years—was a great moment, and I would say this is the fifth. That's the truth."
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