identifying packages with persistent state

We're experimenting with select-level TAF under Oracle 10.2.0.3 for some of our reporting applications, most of which aren't RAC/failover-aware. It's working fairly well so far, but I can foresee some possible issues triggered by packages which have a persistent state. An admittedly contrived example:

create or replace package test_pkg as

   function invocations return number;
end test_pkg;
/

create or replace package body test_pkg as

   cnt number(38) := 0;

   function invocations return number is    begin

      cnt := cnt + 1;
      return cnt;

end test_pkg;
/

Is there a good and/or easy way to query for these beasties? I'd like to identify the potential candidates up-front if possible.

Thanx!

-- 
"I'm too sexy for my code." - Awk Sed Fred.

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