Some doubts related to the installed demo of Typo3 web site -

i have installed typo3 (using introductionpackage-6.1.1.zip package) on local apache web server on ubuntu , appear me demo website.

the strange thing in demo website have horizontal menu (in header) having following elements: started, typo3, features, etcetc

but if click these links obtain following error message:

not found  requested url /typo3/about-typo3/ not found on server. 

except get started link take me on homepage

why? normal? think should exist sample pages related these links

someone can me?

tnx

andrea

check if have mod_rewrite enabled on apache web server , if .htaccess correctly in use