Starting Tomcat 4.1.24 produces this exception:

"ServerLifecycleListener: createMBeans: MBeanException
java.lang.IllegalArgumentException: Not a valid Java type name:
java.lang.String[]
        at
javax.management.MBeanInfo.mustBeValidJavaTypeName(MBeanInfo.java:472)
        at
javax.management.MBeanAttributeInfo.<init>(MBeanAttributeInfo.java:107)
        at
javax.management.modelmbean.ModelMBeanAttributeInfo.<init>(ModelMBean
AttributeInfo.java:233)
        at
org.apache.commons.modeler.AttributeInfo.createAttributeInfo(Attribut
eInfo.java:236)"

The problem is that JMX 1.2 (the version included in Tiger) expects the declared type string for an array-valued attribute to use the JVM syntax, e.g. "[Ljava.lang.String;", while Tomcat is using the Java language syntax "java.lang.String[]". The JMX spec doesn't clearly specify whether one or the other is correct, and prior to JMX 1.2 the RI didn't check this string at all.

Note: the subcategory of this bug should be classes_jmx, but that doesn't exist yet.