gistfile1.diff

diff --git a/mcs/class/System.Web/System.Web.UI/MasterPage.cs b/mcs/class/System.Web/System.Web.UI/MasterPage.cs
index f3327f9..304d12d 100644
--- a/mcs/class/System.Web/System.Web.UI/MasterPage.cs
+++ b/mcs/class/System.Web/System.Web.UI/MasterPage.cs
@@ -33,6 +33,7 @@ using System.Collections;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Web.Compilation;
+using System.Web.Hosting;
 using System.Web.Util;
 using System.Web.UI.WebControls;
 using System.IO;
@@ -111,6 +112,9 @@ namespace System.Web.UI
                internal static MasterPage CreateMasterPage (TemplateControl owner, HttpContext context,
                                                             string masterPageFile, IDictionary contentTemplateCollection)
                {
+                       var req = context.Request;
+                       if (req != null)
+                               masterPageFile = HostingEnvironment.VirtualPathProvider.CombineVirtualPaths (req.CurrentExecutionFilePath, masterPageFile);
 #if TARGET_JVM
                        MasterPage masterPage = MasterPageParser.GetCompiledMasterInstance (masterPageFile,
                                                                                            owner.Page.MapPath (masterPageFile),
diff --git a/mcs/class/System.Web/System.Web.UI/MasterPageParser.cs b/mcs/class/System.Web/System.Web.UI/MasterPageParser.cs
index 72e883b..6558fb6 100644
--- a/mcs/class/System.Web/System.Web.UI/MasterPageParser.cs
+++ b/mcs/class/System.Web/System.Web.UI/MasterPageParser.cs
@@ -103,9 +103,11 @@ namespace System.Web.UI
                                } else {
                                        string path = GetString (atts, "VirtualPath", null);
                                        if (!String.IsNullOrEmpty (path)) {
-                                               if (!HostingEnvironment.VirtualPathProvider.FileExists (path))
+                                               var vpp = HostingEnvironment.VirtualPathProvider;
+                                               if (!vpp.FileExists (path))
                                                        ThrowParseFileNotFound (path);
-                                               
+
+                                               path = vpp.CombineVirtualPaths (VirtualPath.Absolute, VirtualPathUtility.ToAbsolute (path));
                                                masterTypeVirtualPath = path;
                                                AddDependency (path);
                                        } else
diff --git a/mcs/class/System.Web/System.Web.UI/PageParser.cs b/mcs/class/System.Web/System.Web.UI/PageParser.cs
index 82769d3..4e61c51 100644
--- a/mcs/class/System.Web/System.Web.UI/PageParser.cs
+++ b/mcs/class/System.Web/System.Web.UI/PageParser.cs
@@ -405,8 +405,10 @@ namespace System.Web.UI
                        if (!String.IsNullOrEmpty (value)) {
                                if (!BaseParser.IsExpression (value)) {
                                        value = System.Web.VirtualPathUtility.Combine(BaseVirtualDir, value);
-                                       if (!HostingEnvironment.VirtualPathProvider.FileExists (value))
+                                       var vpp = HostingEnvironment.VirtualPathProvider;
+                                       if (!vpp.FileExists (value))
                                                ThrowParseFileNotFound (value);
+                                       value = vpp.CombineVirtualPaths (VirtualPath.Absolute, VirtualPathUtility.ToAbsolute (value));
                                        AddDependency (value);
                                        masterPage = new MainDirectiveAttribute <string> (value, true);
                                } else