mozilla wheel- 3rd button behaviour

[Tom Allison <tallison@tacocat.net>]

From my XF86Config:
Section "InputDevice"
        Identifier      "Configured Mouse"
        Driver          "mouse"
        Option          "CorePointer"
        Option          "Device"                "/dev/psaux"
        Option          "Protocol"              "ImPS/2"
        Option          "ZAxisMapping"          "4 5"
EndSection


Now, when I used to use my wheel for a 3rd button 'click' on Mozilla it 
would open the link in a tab.

Unfortunately now when I hit that button, especially from google.com, I 
get a random-ish page ( usually from somewhere way back in my page 
history or bookmarks ) popping into the current web page and nothing of 
a TAB.

It's really pissing me off.

But I can't imagine what it might be caused by.
It's strange.