The default X-Window server in Debian GNU/Linux Testing (Etch) is now X.Org. The XFree86 was abandoned due a license change (what a stupid change!).

To enable tap and drag actions on the touchpad, install the xfree86-driver-synaptics package, and configure the relevant section in /etc/X11/xorg.conf as follow:

Section "InputDevice"
        Identifier      "Configured Mouse"
        # Driver        "mouse"
        Driver          "synaptics"
        Option          "CorePointer"
        Option          "Device"                "/dev/gpmdata"
        # Option        "Protocol"              "IntelliMouse"
        Option          "Protocol"              "auto-dev"
        Option          "Emulate3Buttons"       "true"
        Option          "ZAxisMapping"          "4 5"
        # Option        "MaxTapTime"            "0"
EndSection

Starting from Debian Squeeze package xserver-xorg-input-synaptics 1.1.1, tapping has been disabled (because it is so by default on many touchpads by upstream). If you want to re-enable tapping you can issue the following command in a terminal:

synclient TapButton1=1
synclient TapButton2=2
synclient TapButton3=3

or you can add a section in /etc/X11/xorg.conf:

Section "InputDevice"
        Identifier      "Synaptics Touchpad"
        Driver          "synaptics"
        Option          "SendCoreEvents"        "true"
        Option          "Device"                "/dev/psaux"
        Option          "Protocol"              "auto-dev"
        Option          "HorizScrollDelta"      "0"
        Option          "TapButton1"            "1"
        Option          "TapButton2"            "2"
        Option          "TapButton3"            "3"
EndSection

Also remember to add a ServerLayout section, otherwise the above section will be ignored:

Section "ServerLayout"
        Identifier      "Default Layout"
        Screen          "Default Screen"
        InputDevice     "Generic Keyboard"
        InputDevice     "Configured Mouse"
        InputDevice     "Synaptics Touchpad"
EndSection

• The synaptics driver: http://web.telia.com/~u89404340/touchpad/
• The X.Org consortium: http://www.x.org/