This resolution is currently not supported in the driver, don't think there is an easy workaround.
I think we can try to squeeze this change in the next release but I'll need the monitor EDID.
The best way to get it is to connect the monitor to a DisplayLink device then send us the logs:
http://support.displaylink.com/knowl...to-displaylink
Or just attach here the .edid file you can find in /Library/Application Support/DisplayLink
Cheers,
Carlo