for an extensive list of ports Sybase seems to use.
an nmap in "default" mode (nmap -sS -O 127.0.0.1) may not be sufficient.
is referenced when you said "I also cannot telnet to this port from a PC."
telnet localhost <port> from the sybase host should work.
on the sybase host
netstat -plaunt | grep base
and look for the sybase port (this assumes the service/daemon is started...) then
nmap -sS -O 127.0.0.1 -p 1024-2048
with an additional
nmap -sS -O 127.0.0.1 -p 2049-4096
The goal here is to find a range of IPs and nmap those. Or just use "the port" you mentioned and skip the whole nmap'ing a range, but use nmap -sS -O 127.0.0.1 -p <port_you_mentioned>
If the sybase port is running and they still cannot connect, they should try
to verify "They" can 'see' the server from client PCs.
Are they behind a corporate firewall, or other another device that may be "in the way"? (Not a firewall as you mentioned)
Please let us know...