NORCROSS, Ga., Sept. 7 -- SpectRx said that Abbott Laboratories Inc. will buy an additional $1 million of its stock as part of a milestone payment, but it agreed to postpone payment of another $1 million. The milestone payments are part of an agreement to commercialize SpectRx's diabetes monitoring device. The SpectRx device is worn on top of the skin and measures glucose levels by using a laser to create microscopic holes, or micropores, and draw samples of interstitial fluid. Norcross, Georgia-based SpectRx said the $1 million stock purchase will increase medical device maker Abbott's common stock ownership in SpectRx to about 5.9 percent. SpectRx said it expects payment of the remaining $1 million before the end of 2002. The second payment and a portion of the first payment are subject SpectRx maintaining its rights to sublicense to Abbott certain technologies it licensed from Altea Development Corp. SpectRx and Altea are currently in arbitration related to their license agreement.