Securing webservices .NET and J2EE

[M.K.A. Monster]

Hi Dwight Peltzer,
Talking about interoperability between .NET and J2EE, we can use WebServices. But what about the security?
We can off-course use a secure connection like SSL. But is this preferable?
And is it already possible to encrypt parts of your XML-data?
Does securing webservice affect the interoperability between .NET and J2EE?
Yours,
Mark Monster

[Dwight Peltzer]

Security does not affect interoperability. NET uses CAS, code access security, and of course, java by nature is secure. Because XML is text, extra precautions must be taken. It does penetrate firewalls, a drawback to XML.

[M.K.A. Monster]

I'm not talking about the webservices code. I'm talking about the XML that is being sent when using the webservice. I want that to be done secure. Are the secure implementations that do not interrupt interoperability?