I managed to fix the problem  - stupidity was on my part - there was an error in
the package  name, in the source.
Afterwards, I was able to deploy, and connect to the bean.

Strangely though, this is what I get after running weblogic.ejbc:

[alex@thinkpad java]$ java  weblogic.ejbc -compiler java
/home/alex/Development/java/jars/tempconv.jar
/home/alex/Development/java/jars/ejbc_tempconv
.jar
<Sep 16, 2002 9:45:06 PM PDT> <Warning> <EJB> <EJB Deployment:
TemperatureConverter has a class
com.alnsab.convert.TemperatureConverterBean which is in the classpath. This
class should only be located in the ejb-jar file.>
<Sep 16, 2002 9:45:06 PM PDT> <Warning> <EJB> <EJB Deployment:
TemperatureConverter has a class
com.alnsab.convert.TemperatureConverterHome which is in the classpath. This
class should only be located in the ejb-jar file.>
<Sep 16, 2002 9:45:06 PM PDT> <Warning> <EJB> <EJB Deployment:
TemperatureConverter has a class
com.alnsab.convert.TemperatureConverter which is in the classpath. This class
should only be located in the ejb-jar file.>
Unrecognized option: -nowarn
Could not create the Java virtual machine.
Exec failed .. exiting

The warnings I understand, but what's up with the '-nowarn' ?