Here’s how to set Thunderbird to automatically launch the correct viewer for any office document attachment:

1) First find out where your open office binaries are, you can do a find “oocalc”, but they should all be in /usr/bin.

/usr/bin/oocalc   (for spreadsheets i.e. xls)
/usr/bin/oodraw  
/usr/bin/ooimpress  (for presentations i.e ppt)
/usr/bin/oowriter  (for docs i.g. docs, docx)

2)  Open an email with an attachment (say one with a spreadsheet) and click on the “Open With..” option and “Browse..” then type in the location of the specific open office app (if its a spreadsheet type in ‘/usr/bin/oocalc’)  and click on “Open”.

3)  Finally click on the ‘Do this  automatically for files..” tick box so you dont have to this again. The “OK”.

That’s it.