How to add an dll to GAC and reference the dll in SSIS Script task?

Hi ,

I am working on a package which needs an external dll.I got the dll file but i don't know how to add an dll to Gac.

I tried gacutil.exe to add an dll but it throws me an gacutil is not recognized as an external or internal command.When i researched on the issue i need to do it from visual studio command prompt tools.But i didn't find the the prompt in tools for visual studio 2008 tools.But i found the gacutil.exe file in C:\Program files(X86)\Microsoft SDKs\Windows\v7.0A\Bin folder.

My question is how can i add the Dll to GAC and reference the Dll in SSIS.

Any help is appreciated.