InvalidDefinitionException when starting a mock

Hello

I try to run a mock which seem to be well configured (i retrieve configuration from a colleague for whom it works) and it always fails first time. Second try, it starts..

I got this error in logs:

Thu Nov 15 11:27:27 CET 2012:ERROR:com.eviware.soapui.impl.support.definition.support.InvalidDefinitionException
com.eviware.soapui.impl.support.definition.support.InvalidDefinitionException
at com.eviware.soapui.impl.wsdl.support.wsdl.WsdlInterfaceDefinition.load(WsdlInterfaceDefinition.java:56)
at com.eviware.soapui.impl.wsdl.support.wsdl.WsdlContext.loadDefinition(WsdlContext.java:66)
at com.eviware.soapui.impl.wsdl.support.wsdl.WsdlContext.loadDefinition(WsdlContext.java:30)
at com.eviware.soapui.impl.support.definition.support.AbstractDefinitionContext.cacheDefinition(AbstractDefinitionContext.java:268)
at com.eviware.soapui.impl.support.definition.support.AbstractDefinitionContext.access$400(AbstractDefinitionContext.java:44)
at com.eviware.soapui.impl.support.definition.support.AbstractDefinitionContext$Loader.construct(AbstractDefinitionContext.java:235)
at com.eviware.soapui.support.swing.SwingWorkerDelegator.construct(SwingWorkerDelegator.java:46)
at com.eviware.soapui.support.swing.SwingWorker$2.run(SwingWorker.java:149)
at java.lang.Thread.run(Unknown Source)


I checked other messages about same error message, but could not find anything that helped.

May you have any idea ? Why does it always fail at first try and start at second try ?
Thank you !

gilles