Hi Naveen,
Please find below log entries for the same error.
01/28/2013 02:34:13 PM HTTP JVM: java.lang.NullPointerException
01/28/2013 02:34:13 PM HTTP JVM: at org.openntf.javacharts.XJFC.getChart(XJFC.java:55)
01/28/2013 02:34:13 PM HTTP JVM: at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
01/28/2013 02:34:13 PM HTTP JVM: at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:60)
01/28/2013 02:34:13 PM HTTP JVM: at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37)
01/28/2013 02:34:13 PM HTTP JVM: at java.lang.reflect.Method.invoke(Method.java:611)
01/28/2013 02:34:13 PM HTTP JVM: at com.ibm.jscript.types.JavaAccessObject.call(JavaAccessObject.java:321)
01/28/2013 02:34:13 PM HTTP JVM: at com.ibm.jscript.types.FBSObject.call(FBSObject.java:161)
01/28/2013 02:34:13 PM HTTP JVM: at com.ibm.jscript.ASTTree.ASTCall.interpret(ASTCall.java:175)
01/28/2013 02:34:13 PM HTTP JVM: at com.ibm.jscript.ASTTree.ASTBlock.interpret(ASTBlock.java:100)
01/28/2013 02:34:13 PM HTTP JVM: at com.ibm.jscript.ASTTree.ASTTry.interpret(ASTTry.java:109)
01/28/2013 02:34:13 PM HTTP JVM: at com.ibm.jscript.ASTTree.ASTProgram.interpret(ASTProgram.java:119)
01/28/2013 02:34:13 PM HTTP JVM: at com.ibm.jscript.ASTTree.ASTProgram.interpretEx(ASTProgram.java:139)
01/28/2013 02:34:13 PM HTTP JVM: at com.ibm.jscript.JSExpression._interpretExpression(JSExpression.java:435)
01/28/2013 02:34:13 PM HTTP JVM: at com.ibm.jscript.JSExpression.access$1(JSExpression.java:424)
01/28/2013 02:34:13 PM HTTP JVM: at com.ibm.jscript.JSExpression$2.run(JSExpression.java:414)
01/28/2013 02:34:13 PM HTTP JVM: at java.security.AccessController.doPrivileged(AccessController.java:284)
01/28/2013 02:34:13 PM HTTP JVM: at com.ibm.jscript.JSExpression.interpretExpression(JSExpression.java:410)
01/28/2013 02:34:13 PM HTTP JVM: at com.ibm.jscript.JSExpression.evaluateValue(JSExpression.java:251)
01/28/2013 02:34:27 PM HTTP JVM: java.lang.NoClassDefFoundError: org.openntf.javacharts.Common
01/28/2013 02:34:27 PM HTTP JVM: com.ibm.xsp.webapp.FacesServlet$ExtendedServletException: java.lang.IllegalStateException: Can't get a Writer while an OutputStream is already in use
regards,
Naseer