Probably the same as you'd do for typing tamil fonts :
1) mkdir -p ~.fonts
2) Copy some tamil fonts into the hidden folder ".fonts"
http://ubuntup.blogspot.dk/2010/08/t...or-ubuntu.html
( Google .. install tamil fonts ubuntu .. )
3) sudo apt-get install ttf-tamil-fonts
4) Restart 'LibreOffice', and all the new fonts should be usable.
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