Hey, hope someone can help me out here? Really confuses me. Well it started when I installed a new motherboard, processor, and memory (Abit NF-M2S, AMD X2 6000). After that when I double clicked in the address bar in Firefox, nothing happened, no highlighting. I checked about:config and all is good. Also, double click no longer opens a folder in Firefox's file browser. Same thing in Seamonkey. But when I double click in a terminal, it highlights the word as expected. Now when I run Geany, double clicking in the text editor will highlight the word, but same problem when it comes to the file browser . At this point I was running 32-bit Slackware 12.2 w/ stock kernel.
Now I've also upgraded to Slackware64 13.0 since the problem happened and the problem remains. I am using the same mouse as I was with the old board....so maybe there's something different about the PS/2 port? Is there some kind of configuration I don't know about? Well thanks to all who read, please help if you can.

OK, I think I may have gotten a hint as to what's wrong. When I click a titlebar in Enlightenment, I see the arrow change to the move cursor. Maybe this means that a click is not being interpreted as a click but instead a holding down of the mouse button? I've also noticed that the keys seem to be a bit more sensitive on the keyboard...

Well now I'm running KDE and having the same problem. I tried messing with the mouse settings but that hasn't helped any. I really don't think it's an X11 problem because I am using the same xorg.conf file as I was before the problem started with "IMPS/2" protocol selected and using the same exact mouse. I don't think it's a kernel issue because I've tried with two different versions and the problem popped up after switching motherboards. So I guess this is just something I have to deal with until I get a new motherboard huh? Going to change Firefox to highlight addresses with single click until something changes...

Finally found the cause of the problem! I was having other weird issues (like when moving large amounts of data from IDE bus to SATA, system would crash) and I figured it was either motherboard or RAM issues. Well after moving my memory to the other RAM slot, things seem to be all good for now! And it looks like the system is running cooler too.