Convert eq-userid to Guid CRM 2011
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Is there an easy way to turn a fetchXML parameter from CRM that is set to "current user" which comes across to the SSRS report as having an "eq-userid" as the operator and no GUID into the GUID of the current user?  I need this to happen before datasets are populated because I use the GUID as a parameter to filter the datasets.  So this likely needs to happen in custom code that is called from a default value of another parameter.  However all the solutions I can find say to add a custom assembly because you need to create a web reference to the CRM webservices.  This seems overly complicated for such a simple use case.  Am I missing something?