Thread:Support/"Fatal exception of type MWException" as answer for "Special:ManageMessageGroups" page

It seems to work fine, except for the page Special:ManageMessageGroups which rturns this message : [17e72b1a] 2013-11-09 16:39:33: Fatal exception of type MWException

and Special:LanguageStats which never publishes.

My configuration is MW 1.21.2 and the latest "MediaWiki Language Extension Bundle" (2013.10).

As I only tried it a few months ago, I tried to suppress and recreate all the tables starting with "translate_" `translate_groupreviews` , `translate_groupstats` , `translate_messageindex` , `translate_metadata` , `translate_reviews` , `translate_sections` , `translate_stash` , `translate_tmf` , `translate_tms` , `translate_tmt` ;

but without success : (

Any idea how to solve this bug ?