Searching I found the following two packages:

1. Tai/Shan for iBus my_SHN-ibus-1.4_keymagic_1.5-1_i386.deb will allow you to add Tai languages (=Shan) to ibus.




2. Tai/Shan fonts for Ubuntu Tai-Fonts-V2.0.0.deb will allow you to read and write shan script

Unfortunately this doesn't solves your problem 100% because ibus doesn't work properly with this package. You can type, but the characters can't be recognised. To solve this problem you could edit the tai-sonla.mim and replace all the "ꪀ" with the right symbols. Maybe someone has a more elegant solutions for this last step.

Keyboard mapping for Tai/Shan on iBus tai-sonla.mim

In the mean time you can also use the fonts in package 2 i.e. A Ying, Kaw Sai, Mongloi, Pang Long, Yunghkio, Tai,X 15-sslm, Ying Ying,Mone Harng Li,Khun jai, MM3 Shan to type shan in applications such as Word and Presentation.

How to install the packages and edit the .mim file:

1 Enable iBus

From Menu, System -> Administration -> Language Support
Under "Keyboard input method system" choose ibus

2 Download all the files

3 Open the .deb packages and select "Install"

4 Edit the .mim file with

sudo gedit /usr/share/m17n/tai-sonla.mim

Change all the "ꪀ" or "ꪀ" with the right tai/shan letters and save the file

You can for example copy them from http://en.wikipedia.org/wiki/Shan_language

5 Add Tai languages i.e. "sonla-kbd" to iBus

From menu, System -> Preferences -> IBus Preferences -> add input method: under the "Tai languages" category, choose "sonla-kbd".

6 Test by opening Word

Open word

Choose "Tai languages - sonla-kbd" by clicking on the keyboard symbol on the right top

If you edit the tai-sonla.mim, please share it again here ;-)