IIS Logging Not Working for WCF Service Calls

We're experiencing a strange phenomenon where IIS logging works perfectly for normal pages in a site but calls to an .svc URL are not being logged.

Example of a URL that is logged -

http://ourserver/HelloWorld.aspx

Example of a URL that is not logged -

http://ourserver/SampleService.svc/echo/helloworld

(In the second example, Echo is a method on the SampleService contract.)

Both URLs perform as expected. The call to the first URL is logged just fine, but the call to the second URL never appears in the IIS开发者_开发技巧 logs. We are only seeing this on IIS6; the same site, when running on IIS7 in a different environment, works perfectly and we see all the expected logging.

It's hard to know if it's a WCF issue or an IIS issue. Does IIS6 have the capacity to exclude certain URL patterns (e.g., .svc) from logging? Are there any known conditions that can cause this sort of "selective logging" to manifest? Any insight would be much appreciated. Thanks,

Jeff