Passwords are hashed, for details on usage of cryptography in BI4.x you can refer to this link here.
http://scn.sap.com/community/bi-platform/blog/2012/02/11/encryption-data-security-in-bi-40
Storing a password for the purpose of authentication in a format where the original password can be retrieved is very bad security practice and not something we do.
As others have said above, you can have someone reset it. BI has a concept of delegated administration, so you can create specific users who will have rights to administer users and reset their passwords, without requiring full administration rights. To do this, grant rights to the special user administrator on the user that they will administer (or on the user management section in CMC, click 'manage top level security' and assign the rights there.).
Even better is to connect to your active directory/LDAP and setup single signon to avoid password management all together.
