Well, the data as typed in excel was "12/01/2005". When I had the
excel cell formatted as mmm-yy (i.e., displaying Dec-05), I got the
error in Word (i.e., the merge field with switches displayed "December
2006"). When I changed the format in the excel cell to mm/dd/yyyy,
there merged data in Word displayed "December 2005".

Now as to connection protocol, I have no idea what you mean. How do I
find out? All I know is I am using the word merge function.