@kol9313: Please provide the following information:
What PostgreSQL ODBC Driver are you using?
What is the schema definition of the PostgreSQL table you are attempting to link into Virtuoso, as I can link tables with int4 and varchar columns into Virtuoso without a problem using the OpenLink PostgreSQL ODBC Driver?
At what point in the linking process is the error occurring?
A Virtuoso trace_on() log so we can see the calls being made in Virtuoso and a PostgreSQL ODBC Driver trace log so we can see the ODBC calls being made to the Postgres database, for analysis.