I can only assume that the name is the problem since you mention it.
Maybe the backslash is interpreted as an escape character. In that case you need to escape the backslash with a backslash.
This is the error I got when I added the backslash to the url:
org.apache.commons.dbcp.DbcpException: java.sql.SQLException: Unknown server host name ‘orbsql\gpd_pilot’.
java.sql.SQLException: Unknown server host name ‘orbsql\gpd_pilot’.
java.net.UnknownHostException: orbsql\gpd_pilot