To quote:

tried uploading a file with a colon (:) in the name on commons; it didn't disallow it, but I got this really unfriendly message:
Internal error
key '2muj1nywb867g7yba09qnnr99h4qos5.' is not in a proper format
Backtrace:
#0 /usr/local/apache/common-local/wmf-deployment/includes/upload/UploadBase.php(557): UploadStash->stashFile('/tmp/phpnXpjgd', Array, NULL)
#1 /usr/local/apache/common-local/wmf-deployment/includes/upload/UploadBase.php(569): UploadBase->stashSessionFile(NULL)
#2 /usr/local/apache/common-local/wmf-deployment/includes/specials/SpecialUpload.php(322): UploadBase->stashSession()
#3 /usr/local/apache/common-local/wmf-deployment/includes/specials/SpecialUpload.php(413): SpecialUpload->showUploadWarning(Array)
#4 /usr/local/apache/common-local/wmf-deployment/includes/specials/SpecialUpload.php(167): SpecialUpload->processUpload()
#5 /usr/local/apache/common-local/wmf-deployment/includes/SpecialPage.php(560): SpecialUpload->execute(NULL)
#6 /usr/local/apache/common-local/wmf-deployment/includes/Wiki.php(254): SpecialPage::executePath(Object(Title))
#7 /usr/local/apache/common-local/wmf-deployment/includes/Wiki.php(64): MediaWiki->handleSpecialCases(Object(Title), Object(OutputPage), Object(WebRequest))
#8 /usr/local/apache/common-local/wmf-deployment/index.php(117): MediaWiki->performRequestForTitle(Object(Title), NULL,
Object(OutputPage), Object(User), Object(WebRequest))
#9 /usr/local/apache/common-local/live-1.5/index.php(3): require('/usr/local/apac...')
#10 {main}

Version: unspecified
Severity: normal