[TYPO3] problem with directmail

[Mirco]

hi,

whenever I try to fetch and compile a page to be sent as an email I 
receive the following error

Warning: fopen(http://www.parkhotel-rosarium.de/'clear.gif'): failed to 
open stream: HTTP request failed! HTTP/1.1 404 Not Found in 
/typo3_src-3.8.1/t3lib/class.t3lib_div.php on line 2099

What's confusing me are these quotes around clear.gif. Does anyone have 
an idea about this problem?

Regards,
Mirco