HTTP JVM: CLFAD0134E: Exception processing XPage request

On our server we keep getting these "informal" errors.. When I consult the error logs they are equally "informal". Since there is quite a large number of XPages and bases, it is not trivial to start commenting out code etc to know where the error is occurring...
Does anybody know WHY,WHAT and WHERE this error occurs? Getting really frustrated with this now..


HTTP JVM: com.ibm.xsp.webapp.FacesServlet$ExtendedServletException: com.ibm.xsp.exception.EvaluationExceptionEx: Error while executing JavaScript computed expression
HTTP JVM: CLFAD0134E: Exception processing XPage request. For more detailed information, please consult error-log-0.xml located in D:/IBM/Lotus/Domino/data/domino/workspace/logs

FROM error-log-0:
View log here