THe HSQLDB-DS.xml file looks like this:

<?xml version="1.0" encoding="UTF-8" ?>
- <!--
The Hypersonic embedded database JCA connection factory config
$Id: hsqldb-ds.xml,v 1.15 2004/09/15 14:37:40 loubyansky Exp $

-->
-
- <local-tx-datasource>
- <!-- The jndi name of the DataSource, it is prefixed with java:/
-->
- <!-- Datasources are not available outside the virtual machine
-->
<jndi-name>DefaultDS</jndi-name>
- <!--
for tcp connection, allowing other processes to use the hsqldb
database. This requires the org.jboss.jdbc.HypersonicDatabase mbean.
<connection-url>jdbc:hsqldb:hsql://localhost:1701</connection-url>


-->
- <!--
for totally in-memory db, not saved when jboss stops.
The org.jboss.jdbc.HypersonicDatabase mbean necessary
<connection-url>jdbc:hsqldb:.</connection-url>


-->
- <!--
for in-process persistent db, saved when jboss stops. The
org.jboss.jdbc.HypersonicDatabase mbean is necessary for properly db shutdown


-->
<connection-url>jdbc:hsqldb:${jboss.server.data.dir}${/}hypersonic${/}localDB</connection-url>
- <!-- The driver class
-->
<driver-class>org.hsqldb.jdbcDriver</driver-class>
- <!-- The login and password
-->
<user-name>sa</user-name>

- <!-- example of how to specify class that determines if exception means connection should be destroyed
-->
- <!-- exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.DummyExceptionSorter</exception-sorter-class-name
-->
- <!-- this will be run before a managed connection is removed from the pool for use by a client
-->
- <!-- <check-valid-connection-sql>select * from something</check-valid-connection-sql>
-->
- <!-- The minimum connections in a pool/sub-pool. Pools are lazily constructed on first use
-->
<min-pool-size>5</min-pool-size>
- <!-- The maximum connections in a pool/sub-pool
-->
<max-pool-size>20</max-pool-size>
- <!-- The time before an unused connection is destroyed
-->
- <!-- NOTE: This is the check period. It will be destroyed somewhere between 1x and 2x this timeout after last use
-->
- <!-- TEMPORARY FIX! - Disable idle connection removal, HSQLDB has a problem with not reaping threads on closed connections
-->
<idle-timeout-minutes>0</idle-timeout-minutes>
- <!--
sql to call when connection is created
<new-connection-sql>some arbitrary sql</new-connection-sql>


-->
- <!--
sql to call on an existing pooled connection when it is obtained from pool
<check-valid-connection-sql>some arbitrary sql</check-valid-connection-sql>


-->
- <!--
example of how to specify a class that determines a connection is valid before it is handed out from the pool
<valid-connection-checker-class-name>org.jboss.resource.adapter.jdbc.vendor.DummyValidConnectionChecker</valid-connection-checker-class-name>


-->
- <!--
Whether to check all statements are closed when the connection is returned to the pool,
this is a debugging feature that should be turned off in production

-->
<track-statements />
- <!--
Use the getConnection(user, pw) for logins
<application-managed-security/>


-->
- <!-- Use the security domain defined in conf/login-config.xml
-->
<security-domain>HsqlDbRealm</security-domain>
- <!--
Use the security domain defined in conf/login-config.xml or the
getConnection(user, pw) for logins. The security domain takes precedence.
<security-domain-and-application>HsqlDbRealm</security-domain-and-application>


-->
- <!-- corresponding type-mapping in the standardjbosscmp-jdbc.xml (optional)
-->
-
<type-mapping>Hypersonic SQL</type-mapping>

- <!-- This mbean can be used when using in process persistent hypersonic
-->
jboss:service=Hypersonic,database=localDB
</local-tx-datasource>
- <!--
This mbean should be used only when using tcp connections. Uncomment
when the tcp based connection-url is used.

1701
true
default
false
true



-->
- <!-- This mbean can be used when using in process persistent db
-->
-
localDB
true




And the file we use as default looks like

-
- <local-tx-datasource>
<jndi-name>DB2DS</jndi-name>
<connection-url>jdbc:db2:mvs.xxxxxx</connection-url>
<driver-class>COM.ibm.db2.jdbc.app.DB2Driver</driver-class>
<user-name>xxxxxx</user-name>
xxxxxxx
</local-tx-datasource>
- <local-tx-datasource>
<jndi-name>jdbc/clr</jndi-name>
<connection-url>jdbc:oracle:thin:@xxxxxxxxxx</connection-url>
<driver-class>oracle.jdbc.driver.OracleDriver</driver-class>
<user-name>orbit_clm</user-name>
orbit_clm
<max-pool-size>20</max-pool-size>
<exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.OracleExceptionSorter</exception-sorter-class-name>
</local-tx-datasource>


I know that the Oracle connection is valid, but I am not sure of the DB2 connection, since that is an older connection string to a legacy application