[TYPO3] HtmlRTE question

[Livius_Agrippa]

Hi,

I tried to insert new classes for internal links.
But without success.
How can I insert new classes and these classes should be visible for the 
desired option?
For example: Right now when I try to insert an internal link in HtmlRTE 
I can select between internal-link and internal-link-new-window. But I 
want to be able to use a new link. How can I do this?

Best regards,
Livius