I'm creating a new issue because the previous issue was closed prematurely without getting my feedback on how to reproduce it (ID: 481518).
This bug is applicable to the .net framework, but I can't see any other way of submitting a bug on .net so I'm posting it here.
Note - this bug looks identical to an IIS related bug (http://support.microsoft.com/kb/293131)
The bug seems to have been introduced by one of the following services packs,
.net 2.0 SP2 or .net 3.0 SP2. The bug does not exist when I've got 2.0 SP1, 3.0 SP1 & 3.5 installed. The bug occurs every time a zero length message is received by my WCF application.