Good news - Bruce Leung Siu Leung plays a villain in Stephen Chow's KUNG FU HUSTLE.

Another old school performer also co-stars- she's Kan Chia Fong from Dragon Claws, Dreadnaught, etc.

Added only Liang.
Sorry, I was not able to find nothing to prove Ms. Kan is in the movie.

They're billing her as Yuen Qiu, she's one of the main players. Her, Bruce Liang, Yuen Wah and Chiu Chi Ling are the martial arts movie veterans. Then there's Chan Kwok Kwan and Lam Tze Chung from Shaolin Soccer. The rest are Chinese actors.
source: www.kungfuhustle.com

KUNG FU HUSTLE (2004)
Stephen Chow Sing Chi
Yuen Wah
Kan Chia Fong (credited as Yuen Qiu)
Bruce Leung Siu Lung
Huang Sheng Yi (female newcomer)
Chan Kwok Kwan
Lam Tze Chung
Dong Zhi Hua (male)
Chiu Chi Ling
Xing Yu (male)
Feng Xiao Gang (male)

Editor: Angie Lam
Composer: Raymond Wong
Cinematographer: Poon Hang Sang
Costume Designer: Shirley Chan
Writer: Stephen Chow, Tsang Kan Cheong, Chan Man Keung, Lola Huo
Producer: Stephen Chow, Chui Po Chu, Jeff Lau
Action Choreographer: Yuen Wo Ping
Director: Stephen Chow

Oops!!!
Sorry!
Added all of them.