You are right about the issue. It is throwing exception when params of type object is passed with value type argument(s). However the issue is fixed and should you require an internal build, please let us know and in that case, please also open up a support ticket (Since we can't send internal builds in public forum) so that we can send you one.
In addition this will also be included in a service pack to be released shortly; therefore you can wait for that as well if not urgent.
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