JOnAS/EasyBeans EJB Pool configurable?

Hi,

yesterday I experimented with JOnAS 5 and @PostConstruct annotation at
SLSB's. As I found out, at initial access of my ear/webapp after
deployment and EJB lookup/invocation;
the @PostContruct-annotated Method is invoked many times, not once as I
would have expected. 

Looking at JOnAS Admin web console, I saw that there are about "15 idle
instances in the pool"  after initial access.

As I did something very memory consuming  in the postconstruct-method
(loading a very large XML document) hich is saved as a member variable
of the SLSB),
I reached OutOfMemoryExceptions very soon -- with 15 instances of this
SLSB in the pool, the XML config was also loaded 15 times into memory.

One quick workaround was to make the config-xml member of the SLSB
"static" and only load it once for all instances, but this is a rather
dirty hack.

Is there a way to configure  the EJB pool for SLSB's so that JOnAS /
EasyBeans do not automatically instantiate 15 instances but only 3 or 5
or so ?

Another solution would be EJB-singleton which holds the config XML, but
as this is part of Java EE 6 I guess this is not available at the
moment?

regards,
HANS