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• Solace Binding: A '>' will not be replaced if it represents the whole topic level and a '*' will not be replaced if it is the last character in the topic level. See also: Solace Binding
• Loopback Binding: A filter level of "..." will not be replaced nor will a '*' found anywhere in the topic level. See also Loopback Binding
• ActiveMQ JMS Binding:: A filter level of ">" or "*" will not be replaced if they represent the whole topic level. Depends on the provider instance ... see JMS Binding

Otherwise any characters that are not alpha-numeric will be replaced. Prior to 3.8, any non alphanumeric character was replaced included the wildcard combinations described above. 

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