Fixed that entering #nnn as parent task should validate (#11979).

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@10658 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/models/issue.rb

@@ -416,7 +416,8 @@ class Issue < ActiveRecord::Base
     end
 
     if attrs['parent_issue_id'].present?
-      unless Issue.visible(user).exists?(attrs['parent_issue_id'].to_i)
+      s = attrs['parent_issue_id'].to_s
+      unless (m = s.match(%r{\A#?(\d+)\z})) && Issue.visible(user).exists?(m[1])
         @invalid_parent_issue_id = attrs.delete('parent_issue_id')
       end
     end