Converted into an actual commandline tool to avoid using custom tasks.

Source/Build.UpdateVersion/Build.UpdateVersion.csproj

@@ -1,59 +1,45 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup Condition="'$(Configuration)' == 'Documentation'">
-    <OutputPath>.</OutputPath>
+    <OutputPath>..\..\Binaries\OpenTK\Release</OutputPath>
+    <DefineConstants>TRACE</DefineConstants>
+    <Optimize>true</Optimize>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)' == 'Debug'">
-    <OutputPath>.</OutputPath>
+    <OutputPath>..\..\Binaries\OpenTK\Debug</OutputPath>
+    <DefineConstants>TRACE;DEBUG</DefineConstants>
+    <Optimize>false</Optimize>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)' == 'Release'">
-    <OutputPath>.</OutputPath>
+    <OutputPath>..\..\Binaries\OpenTK\Release</OutputPath>
+    <Optimize>true</Optimize>
+    <DefineConstants>TRACE</DefineConstants>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)' == 'Nsis'">
-    <OutputPath>.</OutputPath>
+    <OutputPath>..\..\Binaries\OpenTK\Release</OutputPath>
+    <Optimize>true</Optimize>
+    <DefineConstants>TRACE</DefineConstants>
   </PropertyGroup>
   <PropertyGroup>
     <ProjectGuid>{75DC22B1-113F-4A66-96B9-2FF8208C10E8}</ProjectGuid>
+    <RootNamespace>Build</RootNamespace>
+    <OutputType>Exe</OutputType>
+    <TargetFrameworkVersion>v2.0</TargetFrameworkVersion>
   </PropertyGroup>
-  <Import Project="..\Build.Tasks\Common.xml" />
-  <Target Name="UpdateVersion">
+  <ItemGroup>
+    <Compile Include="Program.cs" />
+  </ItemGroup>
+  <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.Targets" />
+  <PropertyGroup>
+    <PreBuildEvent>
+    </PreBuildEvent>
+    <PostBuildEvent>
+    </PostBuildEvent>
+  </PropertyGroup>
+  <Target Name="BeforeBuild">
     <Delete Files="..\..\Version.txt" />
-    <GenerateAssemblyInfo
-      OutputFile="..\GlobalAssemblyInfo.cs"
-      AssemblyCompany="The Open Toolkit Library"
-      AssemblyProduct="The Open Toolkit Library"
-      AssemblyCopyright="Copyright © 2006 - 2010 the Open Toolkit Library"
-      AssemblyTrademark="OpenTK"
-      Major="1"
-      Minor="0" />
-<!-- Fails because xbuild does not respect %3b
-    <DateStamp>
-      <Output TaskParameter="Date" PropertyName="ShortDate" />
-    </DateStamp>
-    <WriteLinesToFile File="..\GlobalAssemblyInfo.cs" Overwrite="true" 
-      Lines='// This file is auto-generated through Build.UpdateVersion.csproj.;
-             // Do not edit by hand!;
-             using System%3b;
-             using System.Reflection%3b;
-             using System.Resources%3b;
-             using System.Runtime.CompilerServices%3b;
-             using System.Runtime.Runtime.InteropServices%3b;
-             ;
-             [assembly: AssemblyCompany("The Open Toolkit Library")];
-             [assembly: AssemblyProduct("The Open Toolkit Library")];
-             [assembly: AssemblyCopyright("Copyright © 2006 - 2010 the Open Toolkit Library")];
-             [assembly: AssemblyTrademark("OpenTK")];
-             [assembly: AssemblyVersion("1.0.0.0")];
-             [assembly: AssemblyFileVersion("1.0.$(ShortDate)")];
-    ' />
--->
   </Target>
-  <Target Name="Build">
-    <CallTarget Targets="UpdateVersion" />
+  <Target Name="AfterBuild">
+    <Exec Command="$(OutputPath)\Build.UpdateVersion.exe" />
   </Target>
-  <Target Name="Rebuild">
-    <CallTarget Targets="Clean" />
-    <CallTarget Targets="Build" />
-  </Target>
-  <Target Name="Clean" />
 </Project>

Source/Build.UpdateVersion/Program.cs

@@ -0,0 +1,90 @@
+#region License
+//
+// The Open Toolkit Library License
+//
+// Copyright (c) 2006 - 2010 the Open Toolkit library.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights to 
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+// the Software, and to permit persons to whom the Software is furnished to do
+// so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+// OTHER DEALINGS IN THE SOFTWARE.
+//
+#endregion
+
+using System;
+using System.IO;
+
+namespace Build
+{
+	class Program
+	{
+        const string Major = "1";
+        const string Minor = "0";
+        static string Version = "{0}.{1}.{2}";
+
+        public static void Main()
+        {
+            GenerateVersionInfo("../../Version.txt");
+            GenerateAssemblyInfo("../GlobalAssemblyInfo.cs");
+        }
+
+        static void GenerateVersionInfo(string file)
+        {
+            // If the file does not exist, create it.
+            if (System.IO.File.Exists(file))
+            {
+                string[] lines = System.IO.File.ReadAllLines(file);
+                if (lines.Length > 0 && !String.IsNullOrEmpty(lines[0]))
+                {
+                    Version = lines[0];
+                }
+            }
+            else
+            {
+                // Build number is defined as the number of days since 1/1/2010.
+                // Revision number is defined as the fraction of the current day, expressed in seconds.
+                double timespan = DateTime.UtcNow.Subtract(new DateTime(2010, 1, 1)).TotalDays;
+                string build = ((int)timespan).ToString();
+                string revision = ((int)((timespan - (int)timespan) * UInt16.MaxValue)).ToString();
+                Version = String.Format("{0}.{1}.{2}.{3}", Major, Minor, build, revision);
+                System.IO.File.WriteAllLines(file, new string[] { Version });
+            }
+        }
+
+        static void GenerateAssemblyInfo(string file)
+        {
+            File.WriteAllLines(file, new string[]
+            {
+                "// This file is auto-generated through Source/Build.Tasks/GenerateAssemblyInfo.cs.",
+                "// Do not edit by hand!",
+                "",
+                "using System;",
+                "using System.Reflection;",
+                "using System.Resources;",
+                "using System.Runtime.CompilerServices;",
+                "using System.Runtime.InteropServices;",
+                "",
+                "[assembly: AssemblyCompany(\"The Open Toolkit Library\")]",
+                "[assembly: AssemblyProduct(\"The Open Toolkit Library\")]",
+                "[assembly: AssemblyCopyright(\"Copyright © 2006 - 2010 the Open Toolkit Library\")]",
+                "[assembly: AssemblyTrademark(\"OpenTK\")]",
+                String.Format("[assembly: AssemblyVersion(\"{0}.{1}.0.0\")]", Major, Minor),
+                String.Format("[assembly: AssemblyFileVersion(\"{0}\")]", Version)
+            });
+        }
+	}
+}