I seek for using LibreOffice Writer or a similar tool as a mail composer and reader in the Evolution.
In Windows Outlook I have used Microsoft Word directly for writing mails. Evolution default mail editor does not enable easy and precise HTML formatting (see comments). One month without answer shows that there is probably no possibility how to configure my present Evolution version (3.2.3) in Ubuntu 12.04 to use the LibreOffice Writer for writing mails and the same Writer or gedit for writing calendar appointment descriptions. I think that many people need it; maybe somebody has so adapted the Evolution source code for his purpose; it would be far more than worth of a bounty of all my reputation. Or, more attention to it will motivate the developers to adapt it in near future.
(I am trying to return to my original question meaning.)