problem close private message tab

[silvercreep]

hello.

I have download the latest version which is 1.4

i put it into my localhost..
and i open it with my browser localhost/phpfreechat-1.4/
then, i try to chat with my friend ( in same network)

the problem is.. when my friend private message me, i cannot close the channel(tab).
it just show the pop up "Are you sure you want close this tab?"
after i click the "ok" button, yet still the channel(tab) does not close at all.

may i know how to solve it? tq.

[chattunnel]

unistall, download the latest version and install.