I am experiencing the same issue. From /var/log/system.log, I see this:
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Apr 8 22:08:53 darpohsh-wsm WindowServer[217]: Warning: Program “nxnode.bin” posted a mouse-down, blocking hardware events, but did no further mouse activity
Apr 8 22:09:24 — last message repeated 24 times —
Apr 8 22:13:27 darpohsh-wsm WindowServer[217]: Warning: Program “nxnode.bin” posted a mouse-down, blocking hardware events, but did no further mouse activity
Apr 8 22:13:28 darpohsh-wsm WindowServer[217]: Warning: Program “nxnode.bin” posted a mouse-down, blocking hardware events, but did no further mouse activity
Apr 8 22:13:53 — last message repeated 10 times —
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