StringUtils.replace is a good function to use here. This is coded to replace the [x0A] with a single space. If there is another character that should be inserted instead, input the character in the last set of quotes within the StringUtils.replace function. Example: StringUtils.replace(value, '[x0A]', '~');
var value = message.getNode('/');
value = StringUtils.replace(value, '[x0A]', ' ');
message.setNode('/', value);