"I don't really know what it is I'm looking at, but I know when it's not right," Jackson, 31, joked to UsMagazine.com at the BAFTA/LA 16th Annual Tea Party on Saturday.
"Honestly, I'm really not that helpful," he added.
"That's not true!" said Kruger, 33. "It's the greatest advice because you know how women can get, you know, that poufy look… and he's like, 'What are you wearing? It makes your butt look like it's as big as a house!'"
Quipped Jackson, "Yeah, like something just vomited on your body!"
"No, he's never that bad," continued Kruger.
Jackson had nothing to do with the pale, tea-length frock Kruger donned to the BAFTA event (shown at left).
"This one you were pretty clear about right from the beginning," Jackson remembered.