There seems to be a severe problem with the cewolf:param tag when running Tomcat 7 (7.0.22 x64) under JDK 7.0.3.
Extract from a huge stack trace, relevant lines are:
org.apache.jasper.JasperException: Unable to convert string "#009900" to class "java.io.Serializable" for attribute "value": Property Editor not registered with the PropertyEditorManager
JSP code is:
<cw:param name="0" value="#009900"/>
<cw:param name="2" value="#ff0000"/>
<cw:param name="1" value="#3399ff"/>
It does not make any difference what the parameter value exactly is, the problem occurs also when passing number (strings), eg. for the Title Enhancer. Switching back to JDK 6.026, everything works fine again.
Apparently Java 7 has Problems converting a string value to Serializable. Part of the problem may be that the setValue() method of ParamTag is overloaded, taking either a String or Serializable as a parameter. I've read somewhere that this may be forbidden by the specs, but didn't look further into this.
Unfortunately, this is kind of a showstopper bug in this scenario, as the entire page fails, and we cannot easily live without the chart postprocessors :-) Meanwhile, we'll stick to Java 6, but we cannot for long, as Oracle announced to terminate support for it in mid-2012. Any help would be greatly appreciated, as this may well also affect others, and CeWolf live charts are quite a great feature.