can't save a rich text TV with 2 images

I created a TV with type rich text
than i fill in in this TV 2 images
than i click save
but what i get is a never ending please wait

any idea

i use
MODx Revolution 2.0.7-pl (traditional)
TinyMCE 4.1.2-pl plugin for MODx Revolution
mysql 5.0.51a-24+lenny4
PHP Version 5.2.14

It could be a problem with mod_security. http://wiki.modxcms.com/index.php/What_is_mod_security_and_how_does_it_affect_me