Last modified: 2010-05-15 15:33:48 UTC
When you go to the move page screen, the "To new title:" field is filled with the current page title encoded in MediaWiki URL format (i.e. with underscores instead of spaces). So, if you click to move "Book of Genesis", the new title field will be filled with "Book_of_Genesis". For page titles consisting of no special characters or spaces the bug will not occur. See bug #766 and SpecialMovepage.php rev. 1.46
Created attachment 176 [details] patch fixes encoding on default title when moving
Reference to bug in original description should be bug #776, not 766
Fixed in REL1_4 and HEAD. Will be available in 1.4beta6. Thanks for the report.