I can create ‘Default HTML Buttons’ (CP-> Admin-> Default HTML Buttons) like <h3></h3> and <a class=“a_extern”></a> and make the definitions in my css.

While publishing my new entry I format it with the my new buttons, but the entry looks like:

<h3>Lorem</h3> ipsum dolor sit amet, <a class=“a_extern”>consectetur </a>adipscing elit, ...
I mean, i just see the Tags in my entry.

Don’t know why it happens. Mybe it’s a kind of chmod-problem.
So, that’s what i made during the Installation.

Installation Instructions:
Set File Permissions

If you are using a Unix server you must set the following files to 666:

path.php
system/config.php
system/config_bak.php
You must set the following directories to 777:

images/uploads/
images/captchas/
system/cache/

and:
system/translations/ to 777

... but maybe there is an other reason for that, any ideas what i made wrong?

Thank you
zebra21

Do you have your weblog set to allow HTML under Admin > Weblog Management?  If it’s not set to allow HTML then EE will translate the “<” character into “&lt;”, for example.

ok, that’s it. the permission was “allow only safe HTML” now i changed it to “allow all HTML” and it’s working.

thank you Chris