Will BES 4.1.6 work with Exchange 2010

Yes it will. I'm not sure if it's supported but it worked for me.

Here is a good link
http://jacobackerman.blogspot.com/2009/12/using-bes-blackberry-enterprise-server.html

Adding more info - http://technet.microsoft.com/en-us/library/gg670940.aspx

Official Exchange support matrix from RIM for BES - http://us.blackberry.com/support/software/server_exchange_ver_jan_6_12.pdf

No, You need BES 5.0 with Service Pack 1 and MU1.

Blackberry notification: http://na.blackberry.com/eng/support/software/server_compatibility.jsp
Microsoft Notification: http://msexchangeteam.com/archive/2009/12/09/453486.aspx

Courtesy:- https://www.experts-exchange.com/questions/26180014/BES-4-1-6-will-support-Exchange-2010.html

Yes, it can work. However upgrading BES is always the best choice.

Here is a work around,just for your reference.

http://jacobackerman.blogspot.in/2009/12/using-bes-blackberry-enterprise-server.html

I am sorry,the above link was already shared.
Sorry Sarasotamac..

I'm sorry everyone.  I will have to take the points on my own question.  I convinced the owner of the company to upgrade everyone to an iPhone.  

Problem solved :)

Ok, but the question was...

Will BES 4.1.6 work with Exchange 2010?

Did we answer the question?

Actually BES 4.1.6 do not work with Exchange 2010.

However,there is a work around for it to work as per this blog,
http://jacobackerman.blogspot.in/2009/12/using-bes-blackberry-enterprise-server.html.

--------
As per RIM,
You need BES 5.0 with Service Pack 1 and MU1 to work with Exchange 2010.

Blackberry notification: http://na.blackberry.com/eng/support/software/server_compatibility.jsp
Microsoft Notification: http://msexchangeteam.com/archive/2009/12/09/453486.aspx