Steps to reproduce:
1 - login in admin2 with admin
2 - click on "Setup" link
3 - click on "Classes" link
4 - click on "Content" link
5 - click on copy icon of "Article"
6 - click on pencil icon of "Copy of Article"
7 - change data:
7.1-Name: Article with comments
8 - Add new attribute:
8.1-select: Comments
8.2-click on "Add attribute" button
9 - click on "OK" button
10- click on "Content struct"
11- create a object of the new class "Article with comments"
12- change data:
12.1-name: Article with comments object
12.2-intro: this is the summary
12.3- check "Show comments"
12.4- check "Enable commenting"
13- click on "Send for publishing" button
14- click on the new object "Article with comments object" link
15- click on "View" link
16- scroll down on preview
17- fill comment fields:
17.1-Name: test
17.2-Email: test@ez.no
17.3-Comment: this is a test
18- click on "Add comment" button
19- verify that the page was redirect http://<you site url>/<admin site access>/<admin site access>/Article_with_comments_object