install scim Ubuntu

Select scim from Synaptic ...

#nano /etc/environment

export XMODIFIERS="@im=SCIM"
export GTK_IM_MODULE="scim"
export XIM_PROGRAM="scim -d"
export QT_IM_MODULE="scim"

Install Vietnamese input method with OpenSolaris

Install SCIM from Package Manager (select all - recommend)

Download

http://www.esnips.com/doc/c05f6a11-563e-4906-9c1a-2ed124cb4aae/scim-tables-vietnamese-ext-0.5.6-16-bin.tar

Extract it, then copy 2 file vi.bin and telex.bin into /usr/share/scim/tables

Then reload scim, choose IMEngine/Global Setup/Disable All, then expand Vietnamese, tick VNI or Telex, expand Others, tick English

Then Apply, OK

Open terminal, type:
#gedit .profile

Add the line: export GTK_IM_MODULE=scim

Save file, then log out

Log on again. You can see system tray icon of SCIM

Open inputable application, left click icon SCIM, choose VNI or TELEX

That's ok

Good luck!