The solution is to add this code in .htaccess when expire setting is enabled:
AddType application/vnd.ms-fontobject .eot
AddType application/x-font-ttf .ttf
AddType application/x-font-opentype .otf
AddType application/x-font-woff .woff
AddType image/svg+xml .svg
ExpiresByType application/vnd.ms-fontobject "now plus 1 week"
ExpiresByType application/x-font-ttf "now plus 1 week"
ExpiresByType application/x-font-opentype "now plus 1 week"
ExpiresByType application/x-font-woff "now plus 1 week"
ExpiresByType image/svg+xml "now plus 1 week"
This for me works perfectly, but I'm not a expert about htacces, so I don't know if this can cause some compatibility issues.
My request is to add this code is next release (of course if this not cause problems)
Regards
Fiorino