check if HTTP_USER_AGENT exists.
check if HTTP_USER_AGENT exists.
qs9816/doophp,phpzxh/doophp,drupalik/doophp,qs9816/doophp,phpzxh/doophp,drupalik/doophp,google-code-export/doophp,phpzxh/doophp,drupalik/doophp,qs9816/doophp,google-code-export/doophp,google-code-export/doophp