my test web.config
<system.serviceModel>
<bindings>
<webHttpBinding>
<binding name="default">
<security mode="TransportCredentialOnly">
<transport clientCredentialType="Ntlm"/>
</security>
</binding>
</webHttpBinding>
</bindings>
<behaviors>
<endpointBehaviors>
<behavior name="JsonBehavior">
<webHttp/>
</behavior>
</endpointBehaviors>
<serviceBehaviors>
<behavior name="LiveTime.Services.TimeReportServiceBehavior">
<serviceMetadata httpGetEnabled="true" />
<serviceDebug includeExceptionDetailInFaults="false" />
</behavior>
</serviceBehaviors>
</behaviors>
<services>
<service behaviorConfiguration="LiveTime.Services.TimeReportServiceBehavior"
name="LiveTime.Services.TimeReportService">
<endpoint address="" binding="webHttpBinding" bindingConfiguration="default"
behaviorConfiguration="JsonBehavior" contract="LiveTime.Services.ITimeReportService" >
</endpoint>
</service>
</services>
<!-- aspNetCompatibilityEnabled should be off, or services wont be able to work concurrently (they will be locked on session)
which leads to noticable perfomance reduction -->
<serviceHostingEnvironment aspNetCompatibilityEnabled="false"/>
</system.serviceModel>