Yes, you can allow tags and their attributes by editing conf/_formatting.php. If you need help, do a search for object or embed here in the forum. It has been discussed quite a bit. Here's a thread to get you started:

http://forums.b2evolution.net/viewtopic.php?t=3297

Well, I'm tring to post a iframe but unsuccesful. The iframe code is :

<!--START JoyOurself IFRAME-->
<iframe
src="http://www.livesexbar.com/livejasmin/joy3tr.html?ID=alinkx"
scrolling="auto" align="middle" width="720" height="170"
frameborder="no" allowtransparency="true" background-color="transparent"></iframe>
<!--END JoyOurself IFRAME-->

and the error message is :

Invalid post, please correct these errors:

Tag iframe is not allowed within tag td
Tag iframe may not have attribute src
Tag iframe may not have attribute scrolling
Tag iframe may not have attribute align
Tag iframe may not have attribute width
Tag iframe may not have attribute height
Tag iframe may not have attribute frameborder
Tag iframe may not have attribute allowtransparency
Tag iframe may not have attribute background-color
Illegal markup found: iframe

=======================================

What should I must change im my formatting.php file to works ?

regards,
Alin