select copy problem [1]

Is there selection option that, when I make the selection, it is automatically put to Selection Buffer without further mouseclicks or keypresses (a-la xterm) ?
I have already tried this option "Options->Genneral->Selection" there is one choice "Copy selected text to the clipboard automatically", but it doesn't work.
xshell continue insert a character "^C" in the current line.

Program Ver. : Xshell 5

Some third party programs make ^C keyboard event to copy text to clipboard when mouse selection occurs.
In my case, it was Yahoo dictionary years ago.