More likely a cache issue.
Go to ~/Library/Caches/com.apple.Safari/Cache.db
Move the Cache.db file to the Trash.
Disabling the Lion "resume" feature will help also since it "caches" web page content.
Open System Preferences > General
Deselect Restore windows when quitting and re-opening apps.
~ (Tilde) character represents the Home folder.
For Lion: To find the Home folder in OS X Lion, open the Finder, hold the Option key, and choose Go > Library
edited by: cs