[TYPO3] be_newsletter with WYSIWYG editor

[bartek]

Hi everybody!
I have the following problem. Seems quite easy but... a little bit 
confusing to me. I have be_newsletter backend module installed which 
provides html newsletter sending capability. All is working fine, but I 
would like to have instead of the standard <textarea>'s (in the "Config 
BE Newsletter section", where I can now place html code of the 
newsletter body), htmlarea-like WYSIWYG editor.
I have installed htmlarea extension and it works fine with the form 
content type in frontend but... i don`t know how to make it work with 
<textarea>'s inside the be_newsletter backend module.
In other words where to put the following code:
-----------------------------
page.headerData.1000 < BG_HTMLAREA_HEAD
page.bodyTagAdd=onload="HTMLArea.replaceAll();"
-----------------------------
which normally, to have it worked with the form content type, I put in 
the TS Setup section on the template for page I want wysiwyg editor on.

If there is no quite easy way to do it or is better way to provide me 
with the possibility to write mails to subscribers of the newsletter in 
wysiwyg editor (maybe another extension which do it), please tell me.

Thank you in advance for any help with that.
Best Regards
Bartek