Yes, I agree. I was using 8.1.7.4 with 9.2.0.4 listener on HP-UX 11i. _____ From: Richard Ji [mailto:richard.c.ji@xxxxxxxxx] Sent: Wednesday, September 21, 2005 2:17 PM To: Goulet, Dick Cc: MGogala@xxxxxxxxxxxxxxxxxxxx; JayMiller@xxxxxxxxxxxxxxxx; oracle-l@xxxxxxxxxxxxx Subject: Re: 10.2 listener won't start on same port as 9.2 listener Well, what you did might not be the same as what I did as it depends on the platform, versions, etc. which I didn't mention in my post. My point was backward compatiblity doesn't always work as advertised. Best regards Richard On 9/21/05, Goulet, Dick <DGoulet@xxxxxxxx> wrote: Humm, Did that too, but without problems. _____ From: Richard Ji [mailto:richard.c.ji@xxxxxxxxx] Sent: Wednesday, September 21, 2005 1:34 PM To: Goulet, Dick Cc: MGogala@xxxxxxxxxxxxxxxxxxxx; JayMiller@xxxxxxxxxxxxxxxx; oracle-l@xxxxxxxxxxxxx Subject: Re: 10.2 listener won't start on same port as 9.2 listener It's backward compatible but not without problems some times. I ran into a problem using 9i listener for a 8.1.7.4 DB where it start to run out of file descriptors. Revert back to 8i listener solved the problem. So I had to run two listeners.