diff --git a/build_support/BuildUtils.rb b/build_support/BuildUtils.rb
index 801de002..0d6739d0 100644
--- a/build_support/BuildUtils.rb
+++ b/build_support/BuildUtils.rb
@@ -17,7 +17,7 @@ def initialize(command, working_directory, framework, flags)
 	def run(assemblies)
 		assemblies.each do |assem|
 			file = File.expand_path("#{@working_directory}/#{assem}")
-			sh "#{@cmd} \"#{file}\""
+			Kernel::system("#{@cmd} \"#{file}\"")
 		end
 	end
 end
@@ -63,7 +63,7 @@ def self.runProjFile(attributes)
 			targetsValue += " /t:#{target}"
 		end
 		
-		sh "#{msbuildFile} #{projFile} #{targetsValue} #{switchesValue}"
+		Kernel::system("#{msbuildFile} #{projFile} #{targetsValue} #{switchesValue}")
 	end
 end
 
@@ -76,7 +76,7 @@ def self.compile(attributes)
 		frameworkDir = File.join(ENV['windir'].dup, 'Microsoft.NET', 'Framework', 'v4.0.30319')
 		aspNetCompiler = File.join(frameworkDir, 'aspnet_compiler.exe')
 
-		sh "#{aspNetCompiler} -nologo -errorstack -c -p #{webPhysDir} -v #{webVirDir}"
+		Kernel::system("#{aspNetCompiler} -nologo -errorstack -c -p #{webPhysDir} -v #{webVirDir}")
 	end
 end
 
@@ -109,4 +109,4 @@ def write(file)
 		  file.puts erb.result(binding) 
 	  end
 	end
-end
\ No newline at end of file
+end
diff --git a/rakefile.rb b/rakefile.rb
index 08aed384..3fc8814c 100644
--- a/rakefile.rb
+++ b/rakefile.rb
@@ -131,18 +131,13 @@ def copyOutputFiles(fromDir, filePattern, outDir)
 	}
 end
 
-task :tests => [:unit_tests]
 
-desc "Runs unit tests (integration tests?, acceptance-tests?) etc."
-task :unit_tests => [:compile] do
-	Dir.mkdir props[:artifacts] unless exists?(props[:artifacts])
+desc "Runs unit tests"
+nunit :tests => [:compile] do |nunit|
 
-	runner = NUnitRunner.new(File.join('src', 'packages', 'nunit.Runners.2.6.3', 'tools',  "nunit-console#{(BUILD_PLATFORM.empty? ? '' : "-#{BUILD_PLATFORM}")}.exe"),
-		'tests',
-		TARGET_FRAMEWORK_VERSION,
-		['/nothread', '/nologo', '/labels', "\"/xml=#{File.join(props[:artifacts], 'nunit-test-results.xml')}\""])
-
-	runner.run ['Magnum.Specs'].map{ |assem| "#{assem}.dll" }
+          nunit.command = File.join('src', 'packages','NUnit.Runners.2.6.3', 'tools', 'nunit-console.exe')
+          nunit.options = "/framework=#{CLR_TOOLS_VERSION}", '/nothread', '/nologo', '/labels', "\"/xml=#{File.join(props[:artifacts], 'nunit-test-results.xml')}\""
+          nunit.assemblies = FileList[File.join("tests", "Magnum.Specs.dll")]
 end
 
 desc "Target used for the CI server. It both builds, tests and packages."