My b2evolution Version: 1.10.x

When I'm writing a new entry and enter a trackback url I get this error:

Warning: Cannot modify header information - headers already sent in /var/www/blogs/tears_blog/blogs/inc/_core/_template.funcs.php on line 133

Warning: Cannot modify header information - headers already sent by (output started at /var/www/blogs/tears_blog/blogs/inc/_core/_template.funcs.php:133) in /var/www/blogs/tears_blog/blogs/inc/_core/_template.funcs.php on line 136

I had this problem with 2.4.0 [rc] and now I upgraded to 2.4.2 -> the same problem again. How can I solve this problem?

Tears