John Miano, founder of the Summit, N.J.-based Programmers Guild, said Monday that he has collected some 1,500 IT job advertisements in the past six weeks from a variety of online jobs boards that express preference for hiring visa holders. Miano said the practice is widespread because "for the most part, there isn't much enforcement going on. So we are trying to do what we can do to bring private enforcement against these employers."

Miano said H-1B workers are in demand because "they are cheap and they make good slave labor." The guild has filed about 100 complaints with the DOJ's Office of Special Counsel for Immigration-Related Discrimination, and it plans to file another 200.

It's not to difficult to find IT job advertisements that seek specific skills, and H-1B opponents have long circulated examples of these advertisements on mailing lists.

For instance, in a search on the job board run by Dice Inc., iGate Mastech, a Pittsburgh-based IT staffing agency with about 1,000 employees, has an advertisement for eight Java developers with three to five years of Java development experience. The ad says: "Only looking for H-1B visas and should be willing to transfer."

The iGate Mastech recruiter listed as the contact for job openings said the ad should have said the positions were open to U.S. job holders and called it a typo. But iGate officials said the job was placed for a U.S. firm that was having trouble finding Java developers.