CRM 2011: Using Xrm.Utility.openEntityForm to pass in both the formid and a parameter... breaks the parameter.

When I send in the form id, the logic works fine but parameter_0 stops working.  If I do not send in the formid, parameter_0 works.  Any idea if I need to adjust my parameter list on the form when I add use the formid to load a given form?

I may have just introduced an error at some point in my code, but from the looks of it, using the formid seems to mess up my parameter's.

Do I need to do something in the form's parameter settings when using the formid like this?  I need to pass in both the formid and the guid of a parent entity, as I have multiple forms for the child entity and I need to use JavaScript to control which one is loaded, but I need to the guid of the parent to perform various logic on the newly opened form and access the parent entity.

This is firing via a ribbon button.  loanId is the guid of the parent entity that is captured when the button is clicked.  Works fine for a single form for the child entity, but doesn't work when using two forms like this.  It seems to break the parameter that I am passing in.  Do I need to adjust the parameter list on the form to account for the formid?

 var parameters = {};
    parameters["formid"] = "2E4E9CB6-74D2-4EFA-877F-35D2140D6AAF";
    parameters["parameter_0"] = loanId;
    Xrm.Utility.openEntityForm("new_hbc", null, parameters);

Any thoughts or suggestions are much appreciated.

Best regards,

Jon Gregory Rothlander