libsm6 6.8.2-10.1 (amd64 binary) in ubuntu hoary

X Window System Session Management library
 libSM provides an interface to XSMP, the X Session Management Protocol.
 XSMP is a protocol that facilitates the management of groups of client
 applications by a session manager. The session manager can cause clients to
 save their state, to shut down, and to be restarted into a previously saved
 state. This protocol is layered on top of the X Consortium's ICE protocol
 (see the libice6 package).