Can’t add a Page with Name 2011

I’ve no idea why i can’t add a Page with Name 2011. WordPress changes the URL Slug to 2011-01.

There is no Post with this Name in my Database. I tried zu flush my rewrite rules but nothing seems to be work.

If i add a Page 2013 it works fine. But only once… If i delete this Page (from Trash) i can’t add it again. WordPress changes the slug to 2013-01. If i change the Post name directly in the database. Nothing happens…

I really wonder why because there is no Post with this Name.

Any suggestions?

This has to do with how paging-within-a-page works. See ticket #5305. There’s a plugin that will allow you to have numeric slugs if you’re willing to sacrifice paging: http://wordpress.org/extend/plugins/allow-numeric-stubs/