[dev-util/monodevelop] "AspNet" addin from "Web Development" category is unavailable

# eix monodevelop
[I] dev-util/monodevelop
     Available versions:  
     (0)    3.0.2-r1 (~)4.2.3[1] (~)5.0.1[1] (~)5.7.0[1] **9999[1]
     (550)  (~)5.5.0.227[2]
     (562)  (~)5.6.2.5[2]
       {doc +git +subversion test}
     Installed versions:  5.7.0[1](19:48:30 19.02.2015)(git subversion -doc)
     Homepage:            http://www.monodevelop.com/
     Description:         Integrated Development Environment for .NET

The problem: when I run monodevelop-5.7.0, there is no AspNet addin under "Web Development" category in "Add-in manager" dialog from "Tools -> AddinManager..." menu.

the file /usr/lib64/monodevelop/AddIns/AspNet/MonoDevelop.AspNet.dll exists and related files (CodeTemplates, Html) are also present.

assembly browser shows

[assembly: AssemblyVersion ("2.6.0.0")]
[assembly: Addin ("AspNet", Namespace = "MonoDevelop", Version = "5.7", Category = "Web Development")]
[assembly: AddinDependency ("Core", "5.7")]
[assembly: AddinDependency ("Ide", "5.7")]
[assembly: AddinDependency ("DesignerSupport", "5.7")]
[assembly: AddinDependency ("Xml", "5.7")]
[assembly: AddinDependency ("SourceEditor2", "5.7")]
[assembly: AddinDescription ("Support for ASP.NET projects, including editing, compiling and previewing")]
[assembly: AddinName ("Web Project Support")]
[assembly: Debuggable (DebuggableAttribute.DebuggingModes.IgnoreSymbolStoreSequencePoints | DebuggableAttribute.DebuggingModes.DisableOptimizations)]
[assembly: AssemblyCopyright ("MIT X11")]
[assembly: AssemblyDescription ("Support for ASP.NET projects, including editing, compiling, previewing and deploying to remote servers.")]
[assembly: AssemblyProduct ("MonoDevelop")]
[assembly: AssemblyTitle ("ASP.NET Project Support")]
[assembly: RuntimeCompatibility (WrapNonExceptionThrows = true)]
[assembly: SecurityPermission (SecurityAction.RequestMinimum, SkipVerification = true)]
[module: UnverifiableCode]

Access attributes are

  -rwxr-xr-x = for MonoDevelop.AspNet.dll
   drwxr-xr-x = for each directory in the path

How to make it work?

gentoo / dotnet

[dev-util/monodevelop] "AspNet" addin from "Web Development" category is unavailable #32