There was a great tip, out of necessity really, about what is effectively a bug in Adobe Illustrator CS4, where Markzware’s FlightCheck Professional can be very handy to assist with. Here is a nice blog post from Bittbox.com which explains it best:

“If you’ve ever run into this annoying little Illustrator problem, it can be very frustrating, but it has a simple fix. Every so often you may find that no matter what color you select, Illustrator converts your selection to grayscale…”
Source: Illustrator 101: The Annoying Grayscale Color Problem

FlightCheck Professional can easily catch if your colors are set to Grayscale, RGB or CMYK. On top of that, FlightCheck can thus of course preflight AND package your entire Illustrator layout or design! Packaging includes all fonts used and placed images; all into a folder with a copy of the original .AI file, even compressing it! OK, back to how to fix this issue, which of course is simple and Bittbox has a nice graphic on how to do it on the link below, but in a nut-shell it is as easy as:  Read more... (278 words, 1 image, estimated 1:07 mins reading time)