[TYPO3] Huge rendering bugs: Very strange behavior with typo3 4.x

[Michael Karrer]

Dear List,

the output of typo3 is sometimes really messed up:
Eg. there is some text after the </body> tag. Or some but not all links 
get displayed as <link id= ... in the frontend.

If i hit the edit button in the backend everything seems ok. To clear 
the frontend and the backend cache does not help.
The only thing which works is to restart the apache httpd server. After 
the this the output is ok again?!?

This is happening to a live installation so any quick help or hints are 
very very welcome!


Data:
------
fedora core 7

I have installed typo3 4.1.5.
The Database is mysql with utf-8 charset.
forceCharset = utf-8
compat_version = 4.1

Mysql is at version 5.0.51
  Database charset is UTF8

Apache Webserver is at version 2.2.6
   DefaultCharset is set to utf-8 in httpd.conf (is this a problem?

php is at version 5.2.4

Please Help!