8e3023aa_all_Control__CCXML_Version_1_0__Details
[Attribute Name] conferenceid [Required] false [Type] string [Details] 
The identifier of the conference to which the dialog was connected to (usually the conferenceid that was specified in the dialogstart or dialogprepare). If the dialog was being connected to a connection the value must be undefined.
Voice Browser Call Control: CCXML Version 1.0