Changing passwords for a Sybase user is a fairly straightforward process. The first example deals with changing the “sa” password (privilege user) or another user's password. The second example is when a user changes their password. Here is the syntax.
Note: If your password string begins with a number, enclose it in "quotes."
# isql -Usa -Ppassword
1> sp_password old_password, new_password, sa
2> go
Changing another user's password
# isql -Usa -Ppassword
1> sp_password old_password, new_password, esofthub
2> go
Any user can change their own password
# isql -Uesofthub -Pesofthub_password
1> sp_password old password, new_password
2> go