Runtime setVariable issue

Environment:

windows 2003, apache-tomcat-7.0.22, jdk1.6.0_25

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		<strong>Steps to reproduce:</strong></p>

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		runtimeAPI.setVariable(uuid, TARGET_PARAM, targetState);</p>

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		runtimeAPI.executeTask(uuid, true);</p>

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		I use the above code to go to next step of process, however the variable is sometimes set with value "org.ow2.bonita.facade.rest.wrapper.RESTObject";<br />
		After I restart the tomcat, the variable sometimes is set with correct value.</p>

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Wich is the type of your variable?

The variable "TARGET_PARAM" is defined in Bonita workflow as Text, and value "targetState" is Java String.