How did you create the "custom" server? Did you copy all the necessary JBoss jar files to this server? The jboss-common-jdbc-wrapper.jar requires jboss.jar too in the classpath. Is the jboss.jar present in the lib folder of your "custom" server?
when i say the jar file is in the class path i mean utility.jar(our custom jar) file not jboss-common-jdbc-wrapper.jar.
Also i have
jboss-common-jdbc-wrapper.jar and jboss.jar are both in C:\jboss-4.0.2\server\custom\lib.
set Java2ClassLoadingCompliance as false and UseJBossWebLoader as false