Google rankings of CMS generated site

Does anyone know how using a CMS impacts on the ranking google generates. Currently the CMS that we are contemplating using generates all its site content from one PHP reference file. This makes for a rather interesting and fairly incoherent URL when referencing sub pages within the site. The point was being made that a much more legible URL makes a positive impact on google ranking. If this is the case is there any advised method of getting around this such as directory redirects using .htaccess files.

http://drupal.org/ is good stuff, according to NickW. he posted about it here:
http://forums.searchenginewatch.com/sho ... php?t=1823

I do not think file extension or filename are super important. make sure you limit the # of variables and / or make your URLs look static.

Just use mod_rewrites to change the URL.

Appreciate it, this is my first time using a CMS, so I really appreciate the advice