I just ran into the same issue and found your post while searching - obviously you've fixed this since it was back in 2010 and but figured I would post what I found in case someone else finds this. :)
I'm using htaccess to redirect my url from mydomaincom/index.php to mydomaincom/ and found that my nav didn't work in Safari since my href addresses where index.php#value and Safari v5 wouldn't carry over the anchor links.
Rather than turn off my redirect I just changed the urls to point to mydomaincom/#value. Not only did this work great for all browsers but it also made my page quicker (not yet sure how but will search this now :))