Find Whether SQL Server 2005 installed is X86 or X64

I want to find whether SQL Server 2005 x86 is installed or SQL Server 2005 x64 is installed programatically(Any API would do.) If anyone can recommend a registry key that I can rely on find whether it is a 32 bit or 64 bit SQL Server that would suffice.

I am building an installer. Based on the version I need to code my install script.

Thanks in advance,

pls do not duplicate the post.........post in any appropriate forum

http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=1889595&SiteID=1

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