MSSQLValidConnectionChecker throws exception with MS SQL Server 2005 JDBC driver

After installing the latest v1.2 version of the MS SQL Server 2005 JDBC driver (http://msdn2.microsoft.com/en-us/data/aa937724.aspx), I've deployed the following datasource

<datasources>
<local-tx-datasource>
<jndi-name>DefaultDS</jndi-name>
<connection-url>jdbc:sqlserver://localhost:1433;DatabaseName=pubs</connection-url>
<driver-class>com.microsoft.sqlserver.jdbc.SQLServerDriver</driver-class>
<user-name>sa</user-name>
<password>jboss</password>
<valid-connection-checker-class-name>org.jboss.resource.adapter.jdbc.vendor.MSSQLValidConnectionChecker</valid-connection-checker-class-name>

<metadata>
<type-mapping>MS SQLSERVER2000</type-mapping>
</metadata>
</local-tx-datasource>
</datasources>

during start-up, the following exception is throwed

2007-10-25 11:26:36,312 DEBUG [org.jboss.ejb.plugins.keygenerator.hilo.HiLoKeyGeneratorFactory] Starting jboss:service=KeyGeneratorFactory,type=HiLo
2007-10-25 11:26:36,328 WARN [org.jboss.resource.adapter.jdbc.vendor.MSSQLValidConnectionChecker] warning: connection validation failed for current managed connection.
2007-10-25 11:26:36,328 WARN [org.jboss.resource.adapter.jdbc.local.LocalManagedConnectionFactory] Destroying connection that is not valid, due to the following exception: com.microsoft.sqlserver.jdbc.SQLServerConnection@9a42ef
com.microsoft.sqlserver.jdbc.SQLServerException: Invalid column name 'x'.
at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDatabaseError(Unknown Source)
at com.microsoft.sqlserver.jdbc.SQLServerStatement.getNextResult(Unknown Source)
at com.microsoft.sqlserver.jdbc.SQLServerStatement.doExecuteStatement(Unknown Source)
at com.microsoft.sqlserver.jdbc.SQLServerStatement$StmtExecCmd.doExecute(Unknown Source)
at com.microsoft.sqlserver.jdbc.TDSCommand.execute(Unknown Source)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.executeCommand(Unknown Source)
at com.microsoft.sqlserver.jdbc.SQLServerStatement.executeCommand(Unknown Source)
at com.microsoft.sqlserver.jdbc.SQLServerStatement.executeStatement(Unknown Source)
at com.microsoft.sqlserver.jdbc.SQLServerStatement.execute(Unknown Source)
at org.jboss.resource.adapter.jdbc.vendor.MSSQLValidConnectionChecker.isValidConnection(MSSQLValidConnectionChecker.java:54)
at org.jboss.resource.adapter.jdbc.BaseWrapperManagedConnectionFactory.isValidConnection(BaseWrapperManagedConnectionFactory.java:445)
at org.jboss.resource.adapter.jdbc.BaseWrapperManagedConnection.checkValid(BaseWrapperManagedConnection.java:231)
at org.jboss.resource.adapter.jdbc.local.LocalManagedConnectionFactory.matchManagedConnections(LocalManagedConnectionFactory.java:200)
at org.jboss.resource.connectionmanager.InternalManagedConnectionPool.getConnection(InternalManagedConnectionPool.java:211)
at org.jboss.resource.connectionmanager.JBossManagedConnectionPool$BasePool.getConnection(JBossManagedConnectionPool.java:500)
at org.jboss.resource.connectionmanager.BaseConnectionManager2.getManagedConnection(BaseConnectionManager2.java:341)
at org.jboss.resource.connectionmanager.TxConnectionManager.getManagedConnection(TxConnectionManager.java:315)
at org.jboss.resource.connectionmanager.BaseConnectionManager2.allocateConnection(BaseConnectionManager2.java:396)

IMPORTANT NOTE: I've been testing against MSSQL Server 2000. This issue might very well not exist at all with MS SQL Server 2005...