Persistent stored in Context

I've got several models that lookup the same persistent.  So, I was
wondering if maybe I should just stash the persistent in the context. 
However, on accomplishing this, I find out that Persistent is not
Serializable, and i get an exception (java.lang.IllegalStateException to
be precise).

I'd appreciate any comments from anyone on wether this is good, bad, or
indifferent (the storing of persistent in the context), to know if I
should proceed with making this work, or just keep passing the key along
in parameters.  I'm usually for the "if it ain't broke, don't fix it"
method of maintenance, but i'm still early in development and would like
to iron it out now if worth it.

TIA
gene