I solved this issue using 2 methods:
1. Using PuTTY Linux version:
Clicking both touchpad buttons, I simulated the middle button.
I needed to enable it manually, since the Linux Mint distro I'm using had not this middle button simulation activated. The latest version of evdev, version 2.5, changed the default for the middle mouse button emulation code. This change has disabled emulation of the middle mouse button by clicking the left and right mouse buttons.
To enable the middle mouse button emulation, add this to
Identifier "middle button emulation class"
Option "Emulate3Buttons" "on"
2. Using PuTTY Windows version
I prefer that since I do not need to change distro settings like Xorg, only Wine settings in order to connect to console serial ports:
Since Wine handles com ports by having a link to the device (i.e.
/dev/ttyUSB0), in the
~/.wine/dosdevices folder, this link would be created as follows, in order to update your wine profile configs:
ln -s /dev/ttyUSB0 ~/.wine/dosdevices/com1
I prefer this second method. Since copying and pasting always works, I do not need the middle button simulation and, the cherry on top of the cake, it NEVER hangs (occasionally PuTTY hangs on some Windows XP installations).
Otherwise, in case you do not need/want to install Wine, the first method is preferable.