The known Flow "Interwiki to somewiki not implemented" exception is generating a lot of exception.log entries. it was about 95% of exceptions today and is skewing our exceptions+fatals graphing. About 85% of the log entries originate on metawiki. There's no user-facing error from these, so Flow should just wfLogWarning() or do nothing when this is the exception, rather than call
\MWExceptionHandler::logException( $e )
The code is includes/Formatter/ContributionsQuery.php line 116 in 1.23wmf15, it moved since 1.23wmf14.
2014-02-22 07:11:30 mw1036 metawiki: [43691a42] /wiki/Special:Contributions/<SomeUser> Exception from line 99 of /usr/local/apache/common-local/php-1.23wmf14/extensions/Flow/includes/Model/Workflow.php: Interwiki to mediawikiwiki not implemented