Code
using System;
using System.Web;
using System.Web.Hosting;

namespace Simone.SharePoint.WcfService
{
    public class WCFVirtualPathProvider : VirtualPathProvider
    {
        public override string CombineVirtualPaths(string basePath, string relativePath)
        {
            return Previous.CombineVirtualPaths(basePath, relativePath);
        }

public override System.Runtime.Remoting.ObjRef CreateObjRef(Type requestedType)
        {
            return Previous.CreateObjRef(requestedType);
        }

public override bool DirectoryExists(string virtualDir)
        {
            return Previous.DirectoryExists(virtualDir);
        }

public override bool FileExists(string virtualPath)
        {
            // Patches requests to WCF services: That is a virtual path ending with ".svc"      
            string patchedVirtualPath = virtualPath;
            if (virtualPath.StartsWith("~", StringComparison.Ordinal) && virtualPath.EndsWith(".svc", StringComparison.InvariantCultureIgnoreCase))
            {
                patchedVirtualPath = virtualPath.Remove(0, 1);
            }
            return Previous.FileExists(patchedVirtualPath);
        }

public override System.Web.Caching.CacheDependency GetCacheDependency(string virtualPath,
                   System.Collections.IEnumerable virtualPathDependencies, DateTime utcStart)
        {
            return Previous.GetCacheDependency(virtualPath, virtualPathDependencies, utcStart);
        }

public override string GetCacheKey(string virtualPath)
        {
            return Previous.GetCacheKey(virtualPath);
        }

public override VirtualDirectory GetDirectory(string virtualDir)
        {
            return Previous.GetDirectory(virtualDir);
        }

public override VirtualFile GetFile(string virtualPath)
        {
            return Previous.GetFile(virtualPath);
        }

public override string GetFileHash(string virtualPath, System.Collections.IEnumerable virtualPathDependencies)
        {
            return Previous.GetFileHash(virtualPath, virtualPathDependencies);
        }

protected override void Initialize()
        {
            base.Initialize();
        }
    }
}

Code
using System;
using System.Web;
using System.Web.Hosting;

namespace Simone.SharePoint.WcfService
{
    public class WCFVPPRegModule : IHttpModule
    {
        static bool virtualPathProviderInitialized = false;
        static object virtualPathProviderInitializedSyncLock = new object();

public void Dispose()
        {
        }

public void Init(HttpApplication context)
        {
            if (!virtualPathProviderInitialized)
            {
                lock (virtualPathProviderInitializedSyncLock)
                {
                    if (!virtualPathProviderInitialized)
                    {
                        WCFVirtualPathProvider vpathProvider = new WCFVirtualPathProvider();
                        HostingEnvironment.RegisterVirtualPathProvider(vpathProvider);
                        virtualPathProviderInitialized = true;
                    }
                }
            }
        }
    }
}

Code
<add name="WcfVirtualPathProvider" type="Simone.SharePoint.WcfService.WCFVPPRegModule,Simone.SharePoint.WcfService, Version=1.0.0.0, Culture=neutral,PublicKeyToken=3e1c8210e1877cc0" />