No refferer problem in log files

[Jon_King]

For some unexplained reason over the last couple of weeks our server logs report the majority of requests as no referrer.

Before the problem we received about 10% no referrers now its at 80%. The total traffic is the same, the rankings are the same, the conversions are the same, the only thing changed are the referrers.

Any idea what is causing this?

[jatar_k]

Have there been any upgrades to apache or the system config, that you know of?