WordPress MU

When i try to write html code to post it disarears (it cuts from post). I'll trying to use some (two or three) syntax highlighters with no effect. It looks like WPMU cuts html from post.
Is it true?
Is there the way to post html code if I want to show it for my readers?

ps. And, please, recommend me GOOD syntax highlighter :) Those I had used - was not so good as Syntax Highlighter from chroder.com (it was for WPSingle v.1.5, and he is not support it now and plugin even disapears from his blog)

Is the Rich Text Editor on or off?

Are you trying to show the actual tag in a post so people can see it? Like < em > this < / em > ?

Rich editing - false.

Don't you think that this is not comfortable to write code like this:
< em > this < / em >
No. I'm trying to write:
<input type="text" name="name" />
But it is not shown - and completely cuts from post. I'm confused...

Have you checked the codex or wp support forum for a plugin?
Codex: http://codex.wordpress.org/Plugins/Syntax_Highlighting

This is an issue in the way WP spits out the posts, I think it has to do with the kses.php, not necessarily a wpmu problem (since mu runs on top of wp). Somebody here might be able to help, but you will probably have a better chance with regular wp support.

Can you not click on the little HTML button in the Write New Post page and edit your HTML code there?