pkgmgr /iu:"TelnetClient"
Applied to Windows 7, Windows Server 2008 R2, Windows Server 2008 or Windows Vista
Package Manager Command-Line Options
The following command-line options are available for Package Manager.
pkgmgr.exe [/?] [/h] [/help] [/l:file_name] [/ip] [/iu:Windows_feature_name] [/m:package_directory] [/n:answer_file] [/norestart] [/o:system_drive_path; offline_Windows_directory_path] [/p:package_name] [/quiet] [/s:sandbox_directory] [/up:package_name] [/uu:Windows_feature_name]
Ref: http://technet.microsoft.com/en-us/library/cc749465(v=ws.10).aspx
