Sinch Nuget package not supported with VS 2010 and framework 4.0 -

when installing nuget package of sinch got un-supported error on vs2010 , framework 4.0

pm> install-package sinch.sms  installing 'sinch.sms 1.1.0.0'.  installed 'sinch.sms 1.1.0.0'.  adding 'sinch.sms 1.1.0.0' dmmservice.  uninstalling 'sinch.sms 1.1.0.0'.  uninstalled 'sinch.sms 1.1.0.0'.  install failed. rolling back...  install-package : not install package 'sinch.sms 1.1.0.0'. trying install package project targets '.netframework,version=v4.0', package doe  s not contain assembly references or content files compatible framework. more information, contact package author.  @ line:1 char:16  + install-package <<<<  sinch.sms      + categoryinfo          : notspecified: (:) [install-package], invalidoperationexception      + fullyqualifiederrorid : nugetcmdletunhandledexception,nuget.powershell.commands.installpackagecommand     pm> 

sorry, right support 4.5