Okay folks, as Farms asked i made it and it works.
http://konight.ru/wmus/code/wpmu_mailer/wpmu_mailer_2.0.txt
.
-> Get the content of a file, create wpmu-mailer.php in wp-content/plugins directory and paste content into it.
.
-> Now, in "Write" menu of administrator panel you'll see a "Spam" link. There you can write a spam for users.
.
-> For default it's test message. No emails will be sent, just testing it.
.
-> If emails are equal for different users it won't send it 2nd time.
.
-> There you can see fast XHTML tags menu (I will not make the TINYMCE Support because it is not working in Opera, but i use it, unless you will ask badly ;p ).
.
-> Default FROM email is email of user â„–1 registered in blog (usually admin :D).
.
-> In Options -> personal options i made a checkbox, which allows you to dont recieve spam. This part was hard, because adding custom options is the part, which not is described in docs AT ALL.
.
-> So i gonna rewrite Avatar plugin (which yu can find somewhere nearly) to make avatar options in personal page too.
.
-> P.S Now all breaks replace with <BR /> tags and e-mail is clear html. If yu really needed in HTML/TXT radiobutton for users... grml... Okay i can do it, but if it needed.
.
-> P.P.S Installation is automatical, just enable plugin and needed table will be created.
.
-> P.P.P.S Lazy to make nice readme page.