XPConnect fails in NS7 but ok in pr1 and mozilla

We have written an XPConnect component which seems to properly load on
mozilla 1.0, 1.0.1, Netscape 7pr1, but not Netscape 7 release.  In
that case the component throws a NS_ERROR_XPC_CI_RETURNED_FAILURE at
create instance time.  Of course NS7 does not ship with xpc shell so
this is difficult to debug.  We are looking for information about
changes that may have been introduced in the netscape 7 that would be
causing this component to fail.

Thanks in advance,

--chris