"ORA-06108: NETTCP" error with WWW applications

Well, I'm back to doing my WWW/Oracle application development, but yesterday, I started getting error "ORA-06108: NETTCP" on any access requests Oracle applications/programs from any other UNIX hosts than the one that the Oracle DB is on. Of course, this error is one of those that is not in the Oracle error message manual. Anybody know what error ORA-06108 is caused by ?

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        Michael D. Grapevine 
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