Prevent microtype tracking to add space between letters?

I use a latex template with small caps for chapter titles. These are spaced a bit using \textls from microtype package. Unfortunately, microtype does not properly increase the tracking but rather add spaces between letters which makes the text unsearchable :(

Do you know of any clean way to set the font tracking? I sounds like it is what microtype is supposed to do…

Possibly the ‘ultimate’ in this field is the microtype, which uses the micro-typography capabilities of current PDFTeX to provide a \textls command, which operates according to parameters declared in a \SetTracking command. Microtype’s ‘tracking’ facility expands the natural spacing font itself, rather than inserting space between characters. Ordinarily, letter-spacing will destroy ligatures; however, this is wrong if the font is of a fraktur style, and the package provides a means of protecting the ligatures in a letter-spaced text.

But it definitely does not with my latex install

This is pdfTeX, Version 3.1415926-1.40.10 (TeX Live 2009)

Package: microtype 2009/03/27 v2.3d Micro-typography with pdfTeX (RS)

You may wonder why I am not using Tex Live 2010… I am not so keen reinstalling all the minionpro package… but if it really helps I'll do it.