ap_proxy: couldn't create the lock

Running Apache 2.0.54 and Weblogic 8.1 SP4 on Solaris 8. Following the
upgrade of the WL-plugin mod_wl_20.so to SP4 version we are getting
intermittent warnings in the apache error log:

[warn] (45)Deadlock situation detected/avoided: ap_proxy: couldn't
create the lock

This is logged when an apache instance is restarted and then
intermittently afterwards.

Havent found anything on this in any apache or WL newsgroups and have
posted at BEA with no response. Does anyone here have any ideas ?

Thanks