Hi,
Yes, with the headers commented out, PHP serves fine. Here's the section:
############################################
## Add default Expires header
##
http://developer.yahoo.com/performance/rules.html#expires
ExpiresActive On
# ExpiresDefault "access plus 1 year"
# ExpiresByType image/x-icon "access plus 1 year"
# ExpiresByType image/png "access plus 1 year"
# ExpiresByType image/gif "access plus 1 year"
# ExpiresByType image/jpg "access plus 1 year"
# ExpiresByType application/x-javascript "access plus 1 year"
# ExpiresByType application/javascript "access plus 1 year"
# ExpiresByType application/js "access plus 1 year"
# ExpiresByType text/css "access plus 1 year"
# ExpiresByType text/html "access plus 1 year"
# ExpiresByType text/xml "access plus 1 year"
# ExpiresByType text/plain "access plus 1 year"
# ExpiresByType image/jpeg "access plus 1 year"
# ExpiresByType text/javascript "access plus 1 year"
I tried uncommenting them one by one, but even after the ExpiresDefault I get the error.
Thanks!