He has already "read the script?"
In a video that TMZ calls, for some reason, "alcohol-fueled," Ken Jeong says a vague, mumbled thing or two about the Hangover 4. In the clip he's caught exiting the Grand Hyatt hotel in Melbourne and whoever's holding the camera (who sounds a little too excited for the occasion) yells at Jeong: "do it again! Ken!" as if he's talking to a seal with a ball ("do-it-again Ken" would be a great nickname, though). Ken Jeong replies, leaning right into the camera with a sharpie and piece of paper he's about to sign forgotten mid-sign, "there you go, buddy there you go!" in an obvious parody of an Australian party guy you might meet partying in Bangkok (the setting of the second Hangover movie). Jeong continues "Hangover 4, Brisbane! There you go, buddy!"
As Jeong is signing more autographs and posing for more photos, the Aussie asks him, "any chance of The Hangover 4?" Jeong, says some unintelligible stuff, of which all it's possible to make out is "Hangover 4...read the script." In response to the next question, "Mr Chow movie?" Jeong simply says, "I would love that." Watch the full video below and, below that, a video to refresh yourself on the character referred to in the video, Leslie Chow.