Another permalink problem!

Hello there! I am facing a permalink problem in my blog..everything seems to work fine except from the pages that have links such as “?author=1” or the source the default gravatar icon [ “wp-content/gravatars/blank_gravatar.png” ] where the link instead of being http://myblog/the_link is http://myblog/the/date/topic_name/the_link. An obvious example of what i am saying is this post : http://iridium.csd.auth.gr/~stpetrak/wordpress/2006/01/04/wiggler-trailer/

where the default gravatar icon is not appeared due to wrong url…

Which php i need to alter to fix the problem? Should i mess with the .htaccess file? Thanks for your patience 🙂