WordPress MU sets some serious limits on users in the system, even going so far as to not allow (by default) common styles to post content. Things like iframes and embeds are understandably not allowed in an open setup.
But there are cases where you may be setting up a system in a closed environment and have had issues with editing the kses.php file, which would have to be re-edited with every upgrade.
Today I found this plugin, Unfiltered MU. I haven’t had a chance to test it yet, but it works in either the mu-plugin folder or the regular plugin folder.
I would strongly caution you to not use this on a public and/or open registration site. It leaves the entire system open to hacking. But for those of you in special circumstances it should do the trick nicely.
(No word yet on whether it allows target=”top” to allow links to open in a new window. 
)
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This plugin is bypass kses.php that filtering some dangerous code. I agree with you Andrea. Never use this plugin if your site is open registration.
I’m just getting into using WP and i was hoping to get your feedback into the difference of using WP verse Drupal, any suggestions to using one over the other?
Thanks for replying to my post Andrea and for the links to research both options… much appriciated!
thanks andrea i guess you rock!
useful information, thanks for sharing
What kind of closed environment would you need a Unfiltered MU for?
tnx for the tip
I’m trying to remove any HTML filter from WordPress. Unfortunately this plugin wasn’t the solution yet