Guys I need to make you aware of a change that causes different registration endpoint identifier lengths to be generated based on the version of ptlib used. GnuGK 2.3.0 (ptlib 2.4.5) registrationConfirm { ... endpointIdentifier = 9 characters { 0034 0033 0039 0035 005f 0065 006e 0064 4395_end 0070 p } GnuGk 2.3.1 (ptlib cvs) registrationConfirm { ... endpointIdentifier = 10 characters { 0034 0033 0039 0035 005f 0065 006e 0064 4395_end 0070 0000 p } While this may not look too much of a problem however if you are registering a h323plus endpoint built off a later version of PTLIB (like PacPhone) on a GnuGk with an earlier version of PTLIB then your endpoint will register but will not be able to make any calls and you will get an error about endpoint not registered. This is because the gatekeeper generated a 9 character endpointIdentifer while the endpoint will send a 10 digit identifier to the gatekeeper. I have patched the latest PacPhone preRelease to resolve the problem www.pacphone.com/downloads/PacPhoneSetup230.exe I will be applying a fix to the H323plus CVS shortly. Simon