I have exactly the same problem described by the OP on a VAIO VPCF111FB. Before kernel 2.6.32-19, the touchpad was detected as if it was a wheel mouse. Touchpad options in kcm-touchpad were grayed out (disabled), but it worked all right, including scrolling. Since 2.6.32-19, the touchpad is detected as an ALPS Touchpad and these settings are editable, but scrolling does not work anymore.
Running Kubuntu 10.04 64 bits fully updated (kernel 2.6.32-21-generic).
I have exactly the same problem described by the OP on a VAIO VPCF111FB. Before kernel 2.6.32-19, the touchpad was detected as if it was a wheel mouse. Touchpad options in kcm-touchpad were grayed out (disabled), but it worked all right, including scrolling. Since 2.6.32-19, the touchpad is detected as an ALPS Touchpad and these settings are editable, but scrolling does not work anymore.
Running Kubuntu 10.04 64 bits fully updated (kernel 2.6.32-21-generic).