I have a client that needs to extract all their data from a
discontinued 16-bit product called Sharkware 4.0 Pro.  Sharkware uses
an old version of SQL Anywhere to store it's data.  The default SQL
Anywhere username and password of dba/sql does not appear to work.

If you can supply me with the correct username and password that
Sharkware 4.0 Pro uses internally to access it's data store, I will
accept the answer immediately.  The question is as above, it is not an
option for the client's data to go to a third party.

Assuming you do not know the password or cannot find it through normal
research, there are some possible approaches for 'white hacking' the
password.  Of course, you will need to acquire the software yourself. 
It is entirely possible that the security for applications from that
era is poor and could be discovered by checking for plaintext
passwords in files, sniffing network traffic or looking within the
memory space of the running application.

Have you tried:

User: MASTER
Password: CONTROL

MASTER/CONTROL did not work.  I a little analysis and I suspect the
username is 'SWAPI', but I could be wrong.

Any other suggestions?