[TYPO3] [RTE] RTE or html parser eating text

[pierrick]

Hello,
 
using version 4.2.1 of Typo3 on a Debian etch server (php 5.2.0-8etch11) we run at a strange issue.
 
After saving some content into the RTE as Text content, when viewing the page is garbaged, some html-tags are not kept as html-tags. For instance, having an explicit <h3>Title</h3> as html code and up having <h3>Title&lt;/h3&gt; as code. The style is then completly messed up. However, when editing, all content is still there.
In some case, paragraphs disappear and are not back in the editor. For instance, pasting a whole text into a new content element and saving, some paragraphs are missing.
 
Does someone have already encountered this issue ?
It appeared after we massivly add contents to the platform and continu to appear on a quite regular basis, but never in same cases. Content is always completly different.
 
If someone does, is there any clue ?
 
Thank you for the help,
Regards,
Pierrick Caillon
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