http://weblogs.asp.net/smguest/archive/2004/08/12/213659.aspx
Good tips on interoperability between .Net and Java webservice, it goes on with defining datatypes in XSD, using NUnit, JUnit for testing, tracing, Date and time comparision , sending differnt datatypes - datamismatch and avoiding null values with sending arrays types, its good on its brief, it has valuable points in Feedback section.