Seen on Ubuntu linux trusty, with Libreoffice packages from Libreoffice.org (not those from the distribution).
May be an issue with Libreoffice.
May be a change in how Libreoffice does things.
May be an issue with LanguageTool that the new version of Libreoffice makes evident.
Crossposting here for reference.
A bug report has been opened on Libreoffice, but they may not give great attention to it since it is related to an unofficial extension.
Sad fact is that since Libreoffice 4.4.3 RC2 Languagetool cannot be used.