Hi Bob,
No, the 'telnet [hostname] 5555' has always worked the same. It is supposed to immediately display a banner, and timeout after about 10 seconds
Actually, everywhere I ever tested this (and I do that quite often), the TCP session instantly connects, then silently waits for 10 seconds, and only then displays the banner and immediately afterwards closes the connection without further ado. I've never seen the banner come up earlier then after the 10s timeout.
Regarding the original poster's problem, excessive delays in connecting TCP sessions may also indicate a borked reverse DNS setup, though it's hard to understand how this should come about as a result of a CORE upgrade. It can be ruled out easily using hosts file entries, though.
HTH,
Andre.