EnvDTE.Project's unique name includes the subfolder inside the solution.

src/AddIns/Misc/PackageManagement/Project/Src/EnvDTE/Project.cs

@@ -56,7 +56,12 @@ namespace ICSharpCode.PackageManagement.EnvDTE
 		}
 	
 		public virtual string UniqueName {
-			get { return Path.GetFileName(FileName); }
+			get { return GetUniqueName(); }
+		}
+		
+		string GetUniqueName()
+		{
+			return FileUtility.GetRelativePath(MSBuildProject.ParentSolution.Directory, FileName);
 		}
 		
 		public virtual string FileName {

src/AddIns/Misc/PackageManagement/Test/Src/EnvDTE/ProjectTests.cs

@@ -134,9 +134,10 @@ namespace PackageManagement.Tests.EnvDTE
 		}
 		
 		[Test]
-		public void UniqueName_ProjectFileNameHasFullPath_ReturnsProjectFileNameWithoutDirectoryPart()
+		public void UniqueName_ProjectInSameFolderAsSolution_ReturnsProjectFileNameWithoutDirectoryPart()
 		{
 			CreateProject();
+			msbuildProject.ParentSolution.FileName = @"d:\projects\myproject\MyProject.sln";
 			msbuildProject.FileName = @"d:\projects\myproject\MyProject.csproj";
 			
 			string name = project.UniqueName;
@@ -144,6 +145,18 @@ namespace PackageManagement.Tests.EnvDTE
 			Assert.AreEqual("MyProject.csproj", name);
 		}
 		
+		[Test]
+		public void UniqueName_ProjectInSubDirectoryOfSolutionFolder_ReturnsProjectFileNameWithContainsSubFolder()
+		{
+			CreateProject();
+			msbuildProject.ParentSolution.FileName = @"d:\projects\myproject\MyProject.sln";
+			msbuildProject.FileName = @"d:\projects\myproject\SubFolder\MyProject.csproj";
+			
+			string name = project.UniqueName;
+			
+			Assert.AreEqual(@"SubFolder\MyProject.csproj", name);
+		}
+		
 		[Test]
 		public void ProjectItemsParent_ParentOfProjectsProjectItems_ReturnsTheProject()
 		{