Application Event Log: Unable to connect publishing custom string handler for output caching.

After adding the Reports Services virtual directories to a sharepoint site/web application you see the below in the event log.

Event Type: Error
Event Source: Office SharePoint Server
Event Category: Publishing Cache
Event ID: 5785
Date: 21/05/2008
Time: 3:01:52 PM
User: N/A
Computer:
Description:
Unable to connect publishing custom string handler for output caching. IIS Instance Id is '1957155781', Url is 'http://localhost/ReportServer/ReportService2005.asmx'.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Cause: microsoft.sharepoint.publishing.publishinghttpmodule is trying to cache an unmanaged path.

Fix: Remove this httpmodule from the ./ReportServer virtual directory web.config.

Steps:
1. Open the web.config file (D:\Program Files\Microsoft SQL Server\MSSQL.1\Reporting Services\ReportServer\web.config)
2. Locate the <httpModules> node, if it's not there create it below the <httpHandlers> node.
3. Add the following <remove name="PublishingHttpModule" />.

Everytime you call a report or the reportserver URL/web service SharePoint tries to turn caching on and it's not a managed path it throws an error, so we need to remove the module in the reportserver.