Are some sites indexed less than others because of ? char

Will questionmark in url have negative effect.

[ski442]

Hi Guys.
I have just been doing a little reading on keyword placements thoughout a web page content and discovered this little phrase.

"Dynamic Pages - any web address that contains a question mark
(i.e. ASP, Perl, Cold Fusion), will not be indexed by the
spiders. "

I am very new seo and keywords placements, but all of my site is dynamic and contains a ? in nearly every url
will this or could this be bad for my ecommerce site.

If posted on wrong board please do move and very sorry.
Thanks in advance and look forward to reading your replies.
Ski442