First, are you using Visual Studio 2005 or 2008? Next if you are using VS2005 did you install the .NET 3.0 CTP tools for WCF/WF that was released in 2006? I ask these questions because I wanted to know how you setup your proxy class in the client. Did you right click and do "add service reference" or "add web reference"
Also, does your WCF config file look similar to the below? This shows a dual setup, both Basic and WsHttp Bindings.
<system.serviceModel>
<bindings>
<wsHttpBinding>
<binding name="wsHttp">
<security mode="None">
<transport clientCredentialType="None" />
<message clientCredentialType="None" negotiateServiceCredential="false" establishSecurityContext="false" />
</security>
</binding>
</wsHttpBinding>
<basicHttpBinding>
<binding name="basicHttp"/>
</basicHttpBinding>
</bindings>
<behaviors>
<serviceBehaviors>
<behavior name="NorthwindBehavior">
<serviceMetadata httpGetEnabled="true" />
<serviceDebug includeExceptionDetailInFaults="true" />
</behavior>
</serviceBehaviors>
</behaviors>
<services>
<service behaviorConfiguration="NorthwindBehavior" name="SampleApplicationWCF.Library.SupplierService">
<endpoint binding="wsHttpBinding" bindingConfiguration="wsHttp" name="wsHttpSupplierService" contract="SampleApplicationWCF.Library.ISupplierService" />
</service>
</services>
</system.serviceModel>