I just purchased and donated one of these special dual-link adapters to the 30" display for Omni, Optik et al to use. The 30" display now resolves natively. It was $107 new.

Please do not remove / unscrew this adapter from the monitor (or otherwise borrow it)?

Thank you,
David.

On Thursday, December 4, 2014, David Keenan <dkeenan44@gmail.com> wrote:
$99:
http://store.apple.com/us/product/MB571Z/A/mini-displayport-to-dual-link-dvi-adapter 

Plugging directly into a 'normal' DVI adapter ie single-link DVI will not support the display's native resolution of 2560x1600. Single-link adapters will instead deliver a maximum of half the supported resolution, 1280x800. Single-link adapters include the typical Apple-style DVI>MiniDP adapter dongle most are used to using.. See:

http://support.apple.com/en-us/HT201927 

So if anyone feels like giving the video group a christmas present of this pricey adapter cable, that'd be really great! It would be kept with the monitor. 

Best,
David