[R] Using {tabularx} latex package with the {xtable} package?

I am trying to solve the problem of having a latex table (produced using the xtable http://cran.r-project.org/web/packages/xtable/index.html, then inserted to a latex file using Sweave), exceeding the margins of my LaTeX document. I found that one such solution can be based on the

Re: [R] Using {tabularx} latex package with the {xtable} package?

with the tabularx LaTeX package. Any other suggestions would be most welcomed. It would be more courteous to the rhelp readers if you let them know you cross-posted this question on SO: http://tex.stackexchange.com/questions/43328/using-tabularx-latex-package-with-the-xtable-package-in-r