Haitians who were visiting in the US when the massive earthquake struck, stranding them here, don't have to fear arrest when their documents run out. However, they must report to the Department of Immigration and Naturalization Service, according to an aid to Congressman Frank Pallone.
Under the Temporary Protected Status provision of the department's rules, Haitian visitors who register with the agency can stay in this country up to about 18 months, if they are unable to return to their homes due to the quake. But they must contact the agency. I'll post those details here as soon as they arrive from the aid.