soap / ssl problem

I am using JDeveloper 9.0.3 and the Oracle SOAP library which is shipped with Oracle JDeveloper.
My application connects to a SSL enabled webservice.

The first problem I encountered was a 'no njssl9 in java.library.path' error.

I used the tips from Lehmann's BLogger site (http://radio.weblogs.com/0132036/2004/02/13.html).
I could not get this working in JDeveloper 9.0.3 because JDev 9.0.3 is using java jdk 1.3 which has not JSSE built in.
So I decided to use JDeveloper 9.0.5.2. which uses the java jdk 1.4.

It works, however now I am stuck with an error that the certificate chain is incomplete.
The webservice to which I connect sends only the 'last' certificate, so not the entire chain. Can this be the problem?

I have a couple of questions:

1) what do I have to do to ensure that my application trusts the webservice SSL certificates. I know I have to install
the certificate somewhere in the cacerts file. But which certificate en how do I store it?

2) Is it true that the Oracle SOAP library only works with the Oracle Wallet? Does that mean I cannot get Oracle SOAP
to work on an Oracle Application Server with my application?

3) Is there any way to solve the 'no njssl9 in java.library.path' error using the Oracle SOAP library in JDeveloper 9.0.3?