Migrated from Smartgwt3.0 to Smartgwt5.0. setHeaderHeight property is not working.

Migrated from Smartgwt3.0 to Smartgwt5.0.

setHeaderHeight is not working with new version. Giving the following exception.

Caused by: com.google.gwt.core.client.JavaScriptException: (TypeError) @com.smartgwt.client.widgets.BaseWidget::setProperty(Ljava/lang/String;F)([string: 'headerHeight', double: 40.0]): this.header is undefined at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:249) at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:136) at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:576) at com.google.gwt.dev.shell.ModuleSpace.invokeNativeVoid(ModuleSpace.java:304).....

Can any one help me in solving this issue.