SOAP over HTTPS using WebSphere

[Raggi Luca <Lu...@usi.unicredit.it>]

I'm trying to expose an Axis SOAP service over HTTPS, but I can't find the way to make it run.
The web service is deployed on a WebSphere 4.0 and the application server is configured to use an IBM HTTP Server installed on a separate machine (in short, the typical configuration with a web server in the DMZ and an application server behind the firewall).  The HTTP Server is set up to use only the secure protocol.  While all of the other servlets and JSPs contained in the same web application work fine, the SOAP service throws a java.net.SocketException, stating "SSL implementation not available".
I think the SSL certificate installation on the web server is correct, since the whole site responds over HTTPS.  Do I need to set up something on the application server too?
Why does the Axis Servlet answer if I call it in HTTPS from a browser but throw this exception when invoked by a SOAP client?
Any suggestion could help.

Thanks,
Luca