How to change the default UserAgent value in Konqueror

I want to change the UserAgent string in Konqueror fore every site visit and not only for a special site. But the interface has not such functionality. It is possible to set it directly in the following file ~/.kde/share/config/kio_httprc by adding the following string on the first line in this file UserAgent=<newAgentName>. NewAgentName has to be replaced by the wished name.