Wikimedia Bugzilla is closed!

Account creation is failing on strategy.wikimedia.org.  It's giving the following error.  Today I noticed that Extension:NewUserWelcome was calling a different template than before - it used to call Template:Welcome and today it is calling Template:Welcome-subject.  I populated that template, thinking it might fix the problem but no such luck.

Internal error
Error in creating title for basename User talk:Philippe.test/_ In other languages: Български (bg) বাংলা (bn) Dansk (da) Deutsch (de) Ελληνικά (el) English (en) Esperanto (eo) Español (es) Euskara (eu) fil (fil) Français (fr) Frysk (fy) עברית (he) Italiano (it) 日本語 (ja) 한국어 (ko) ქართული (ka) Ripoarisch (ksh) Latviešu (lv) Македонски (mk) Malti (mt) नेपाली (ne) Nederlands (nl) Norsk (bokmål)  (no) Occitan (oc) Kapampangan (pam) Polski (pl) Português (pt) Русский (ru) Slovenčina (sk) Svenska (sv) _ Add translation _edit___Welcome to the Wikimedia Foundation's strategic planning process. We appreciate your interest in taking part. You can start by reading our Community guidelines. Check out the links on the Main Page and find an area that interests you. Please feel free to ask me any questions, or you may leave a message on the Village pump. ___
Backtrace:
#0 /usr/local/apache/common-local/wmf-deployment/extensions/LiquidThreads/classes/Threads.php(193): Threads::incrementedTitle('User talk:Phili...', 90)
#1 /usr/local/apache/common-local/wmf-deployment/extensions/NewUserMessage/NewUserMessage.class.php(93): Threads::newThreadTitle('<div style="cle...', Object(Article))
#2 [internal function]: NewUserMessage::createNewUserMessage(Object(User), false)
#3 /usr/local/apache/common-local/wmf-deployment/includes/Hooks.php(133): call_user_func_array(Array, Array)
#4 /usr/local/apache/common-local/wmf-deployment/includes/specials/SpecialUserlogin.php(200): wfRunHooks('AddNewAccount', Array)
#5 /usr/local/apache/common-local/wmf-deployment/includes/specials/SpecialUserlogin.php(112): LoginForm->addNewAccount()
#6 /usr/local/apache/common-local/wmf-deployment/includes/specials/SpecialUserlogin.php(17): LoginForm->execute()
#7 [internal function]: wfSpecialUserlogin(NULL, Object(SpecialPage))
#8 /usr/local/apache/common-local/wmf-deployment/includes/SpecialPage.php(791): call_user_func('wfSpecialUserlo...', NULL, Object(SpecialPage))
#9 /usr/local/apache/common-local/wmf-deployment/includes/SpecialPage.php(559): SpecialPage->execute(NULL)
#10 /usr/local/apache/common-local/wmf-deployment/includes/Wiki.php(254): SpecialPage::executePath(Object(Title))
#11 /usr/local/apache/common-local/wmf-deployment/includes/Wiki.php(64): MediaWiki->handleSpecialCases(Object(Title), Object(OutputPage), Object(WebRequest))
#12 /usr/local/apache/common-local/wmf-deployment/index.php(117): MediaWiki->performRequestForTitle(Object(Title), NULL, Object(OutputPage), Object(User), Object(WebRequest))
#13 /usr/local/apache/common-local/live-1.5/index.php(3): require('/usr/local/apac...')
#14 {main}