Tag BeginString not present in the FIXML spec

Imported from previous forum

In the Fixml 4.1 DTD is not defined the tag BeginString wich is present in FIXimate - FIX 4.1 Message and Tag Explorer (XML). Is the value FIX 4.2 an attribute of BeginString (the BeginString tag is define as an Empty tag) or is the value contained in the tag (the BeginString tag contain a #PCDATA)?