>microtype is the main pacakge that provides this facility in LaTeX. >Whether it works with xetex, etc, I do not know.
http://www.archivum.info/comp.text.tex/2008-07/00438/Re:_Character_protruding_with_xelatex suggest that neither microtype or pdfcprot works for xetex. I guess you have to choose either pdflatex or xelatex... for the time being. Ingar
