Anyone know what the following error means and how to get it fixed?

[tuckerpm]

I'm using SmartGWT 3.1 and GWT 2.5.1 and running in IE9 mode in IE10.

This started happening after I deleted the auto generated project folder.

Caused by: com.google.gwt.core.client.JavaScriptException: (TypeError) @com.smartgwt.client.widgets.toolbar.ToolStripMenuButton::create()([]): Unable to get property 'extractFromConfigBlock' of undefined or null reference
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:571)
at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:279)
at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeObject(JavaScriptHost.java:91)
at com.smartgwt.client.widgets.toolbar.ToolStripMenuButton.create(ToolStripMenuButton.java)
at com.smartgwt.client.widgets.BaseWidget.getOrCreateJsObj(BaseWidget.java:386)
at com.smartgwt.client.widgets.layout.Layout.addMember(Layout.java:1228)
at com.smartgwt.client.widgets.toolbar.ToolStrip.addMenuButton(ToolStrip.java:451)