https://bugzilla.redhat.com/show_bug.cgi?id=524428 is my Fedora 12 bug report on this, but I suspect it is an upstream problem, so I thought I should report it here as well. If I try to make button 8 a drag lock for button 1, the results are the wild and wacky results described in the redhat bugzilla above. If I try to make button 8 a "universal" drag lock, using xinput set-int-prop \ 'Kensington Kensington Expert Mouse' \ 'Evdev Drag Lock Buttons' 8 8 It works better, but I have to click 8 then 1 to get out of the drag lock as well as to get into it (which seems silly - I'd think that just click 1 or click 8 by itself would end the drag lock). I'm still forced to disable evdev and go back to the old way of defining drag lock to get my mouse in a usable state.
Thanks, indexing in the property handler was wrong and the numbers weren't assigned to the right buttons. Fix pushed as 11669d82790fd7c94c44c0d487d3fa5e203528e9, at least for the multiple drag-lock button issue. The other issue requires a bit more subtle changes to make sure we release the right buttons. Please file a new bug and add it to Bug 16699 (evdev feature request tracker). Note that the backlog is pretty bad at the moment, so it's probably best if you try to implement the feature yourself.
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