Recording this as a memory jogger in case I see it again...
" Msg 7346, Level 16, State 2, Line 1
Cannot get the data of the row from the OLE DB provider "ADSDSOObject" for linked server "linkedservername".
Could not convert the data value due to reasons other than sign mismatch or overflow. "
Was retrieving data from Active Directory via a linked server in SQL.
Bottom line is that you cannot use OPENQUERY to get multivalued attributes or columns containing date information from AD.