(at least one) older versions allowed entering pages in the "Special:" space (-1) into the watchlist. with version 1.18, trying to edit the watchlist looks for the corresponding talk page of all the pages in current list, and since "Special:" pages do not have talk pages associated with them, this creates the following exception when trying to use "View and edit watchlis":

the problem can be reproduced by using the API to insert a page in the "Special:" space into the watchlist, e.g. by running the following javascript code:

<code>
$.post(mw.util.wikiScript('api'), {action: 'watch', title: 'Special:Recentchanges', token: mw.user.tokens.get('watchToken')})
</code>

(you'll need to run it again with "unwatch" to make your watchlist editable again).

here is the exception:

<pre>
getTalk does not make any sense for given namespace -1
Backtrace:
#0 /usr/local/apache/common-local/php-1.18/includes/Namespace.php(84): MWNamespace::isMethodValidFor(-1, 'MWNamespace::ge...')
#1 /usr/local/apache/common-local/php-1.18/includes/Title.php(2850): MWNamespace::getTalk(-1)
#2 /usr/local/apache/common-local/php-1.18/includes/specials/SpecialEditWatchlist.php(182): Title->getTalkPage()
#3 /usr/local/apache/common-local/php-1.18/includes/specials/SpecialEditWatchlist.php(149): SpecialEditWatchlist->showTitles(Array, '?????????? ????...')
#4 [internal function]: SpecialEditWatchlist->submitRaw(Array)
#5 /usr/local/apache/common-local/php-1.18/includes/HTMLForm.php(279): call_user_func(Array, Array)
#6 /usr/local/apache/common-local/php-1.18/includes/HTMLForm.php(228): HTMLForm->trySubmit()
#7 /usr/local/apache/common-local/php-1.18/includes/HTMLForm.php(242): HTMLForm->tryAuthorizedSubmit()
#8 /usr/local/apache/common-local/php-1.18/includes/specials/SpecialEditWatchlist.php(76): HTMLForm->show()
#9 /usr/local/apache/common-local/php-1.18/includes/SpecialPageFactory.php(460): SpecialEditWatchlist->execute('raw')
#10 /usr/local/apache/common-local/php-1.18/includes/Wiki.php(224): SpecialPageFactory::executePath(Object(Title), Object(RequestContext))
#11 /usr/local/apache/common-local/php-1.18/includes/Wiki.php(624): MediaWiki->performRequest()
#12 /usr/local/apache/common-local/php-1.18/includes/Wiki.php(531): MediaWiki->main()
#13 /usr/local/apache/common-local/php-1.18/index.php(57): MediaWiki->run()
#14 /usr/local/apache/common-local/live-1.5/index.php(3): require('/usr/local/apac...')
#15 {main}
</pre>

Version: 1.18.x
Severity: normal