What I did was to install the "Easy Debian Turbo Charged Edition". Then I install scim inside debian (instead of installing maemocjk inside maemo). Just open a terminal inside debian, and enter:
sudo apt-get update
sudo apt-get install scim-pinyin

To make scim the default input, enter the following lines in ~/.chroot file:
export XMODIFIERS="@im=SCIM"
export XIM_PROGRAM=/usr/bin/scim -d
export GTK_IM_MODULE=scim
export QT_IM_MODULE=scim

Reboot, and it should work.

When I need to enter Chinese, I just use the equivalent Debian apps (leafpad, stardict, firefox etc). Your don't have to run them inside the LXDE environment, you can simply run it within maemo The hildon keyboard will not be replaced by matchbox keyboard anymore!