For a moment, the Ethiopian-born activist seemed to melt into the crowd, blending into the sea of black professors, health experts and community leaders. But when he suggested focusing some attention on African immigrants, the dividing lines were promptly and pointedly drawn. The focus of the campaign, activist Abdulaziz Kamus was told, would be strictly on African-Americans. "`I said, `But I am African and I am an American citizen; am I not African-American?' '' asked Kamus, an advocate for African immigrants.