Have you seen this article in the International Herald Tribune?
In recent months, Xuzhou Anying appears to have posted several requests on online trading sites seeking to purchase large quantities of melamine.
In one March 29 posting on a trading site operated by Sohu.net, a Chinese Web site, people who said they were with Xuzhou Anying wrote, "Our company buys large quantities of melamine scrap all year around." There were also postings on several other online trading sites, like ChemAbc.net.
The composition of that "melamine scrap" might explain the "red crystals" seen in the Cornell samples.
Interesting article, to say the least. If credible, it confirms the theory that the melamine was added deliberately, and also explains how and why a substance that has been described in previous reports as "relatively expensive," and therefore not economically feasible, was used.
My bad.
Like China (IHT is a PRC publication) cares about violating all of our copyrights.