In Meetme.conf

[generals]

[rooms]
conf => 555


In extension.conf

exten => 555,1,MeetMe(555,i,1234)



But When I dial 555 than Its says wrong number and in asterisk -r it shows me 

[Nov 23 13:09:43] WARNING[28218]: pbx.c:1797 pbx_extension_helper: No application 'MeetMe' for extension (default, 555, 1)
  == Spawn extension (default, 555, 1) exited non-zero on 'SIP/harpal-081d5378'
[Nov 23 13:09:43] NOTICE[28218]: cdr.c:434 ast_cdr_free: CDR on channel 'SIP/harpal-081d5378' not posted