Knime server drive

Hi.

When i try to execute a workflow on knime server, i'm getting this error:

Execute failed: Could not create connection to database: Could not find driver class: com.microsoft.sqlserver.jdbc.SQLServ

When i execute on a local machine, it works. Anyone knows where can i put the driver so knime server can recognize?

This is described in the Server Administration Guide in section "Preferences File".