Jt400jar JDBC connection to AS400


I’m strugeling with the task of connecting to an AS400 with my Integration Server using the jt400.jar JDBC Driver.
I have downloaded the jt400.jar file to the C:\IntegrationServer\webMethods\IntegrationServer4\lib\jars folder and restarted. When I’m trying to create an database alias in the Administrator I use the following parameters.

DB URL: jdbc:as400://
Username: XXXX
Password: Cant tell you obviusly.
JDBC Driver: com.ibm.as400.access.AS400JDBCDriver
Min num of sessions: 5
Max num of sessions: 15
Expiration time: “Blank”
Loaded Driver: com.ibm.as400.access.AS400JDBCDriver

When I try to connect nothing happens. The browser is working but dosent get any answer.
Is there someone out there that knows what I did wrong?