According to our programmers, we cannot control how the browser opens.
If you are using IE, you can set the browser to open links in the current tab or window. To do this, go to Tools->Internet Options. On the General tab click the Settings button in the Tabs section. Next, in the 'Open links from other programs in:' section, select the 'The current tab or window' option.
In FireFox, the best you can do is set it to open in a new tab instead of new window. To do this, go to Tools->Options. Select Tabs, and then check the 'a new tab' option.
I hope this helps!