f is not a valid bitstring

I have an entity bean that uses a boolean for a field, and that boolean maps to a bit field in the database.  Is this the proper field I should be mapping to?  Under Sybase and MSSQL 7, there were no problems with sending "true" or "false" through the bean - something took care of it and mapped it properly.  Under Postgres 7.0.3, however, I consistently get this error:

java.sql.SQLException: ERROR:  zpbit_in: f is not a valid bitstring

I've traced it back, and found that it's taking the first letter of the boolean value and trying to put that into the bit field instead of changing it to a 1 or 0.  Any suggestions?

Thanks a bunch...

Walt Skidmore