ORA-04031 with Oracle 8.1.7.0.0 on HP-UX 11.0. URGENT

Getting:
"ORA-04031: unable to allocate 4256 bytes of shared memory ("shared pool", "unknown object", "sga heap", "library cache")" and
"ORA-00604: error occurred at recursive SQL level 1" over and over in the alert log.

This is a "suddenly" event on a production database that had been operational at 8.1.6 for a year, and is now at 8.1.7 for a month. Running SilverStream as a front-end, which has about 70 dedicated connections in it's pool (SilverStream does MTS on its own).

SilverStream users are unable to login.
I'm unable to login "sqlplus sys/manager", getting end-of-communication channel.
I'm unable to login "sqlplus internal", getting already logged in. I'm able to login "svrmgrl", but most commands end the session with a "not connected".
  "startup" gives the expected already started, shutdown first.

My questions are (yeah, I know, clairvoiance):

• Could anyone who experienced this share solution(s)?
• Will a "shutdown immediate" just hang?
• Will a "shutdown abort" cause harm? (Nothing but once-a-day full export.)
• What would you do?

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Author: Kirsch, Walter J (Northrop Grumman)
  INET: walter.kirsch-eds_at_eds.com

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