Masquerade ???

Hi all,
I'm trying to MASQUERADE my mails.so that mails will appear as
laks@dev.com
rather than,
laks@devserver.caa

I tried changed following lines in sendmail.mc file,

MASQUERADE_AS(dev.com)dnl
FEATURE(masquerade_envelope)dnl
FEATURE(masquerade_entire_domain)dnl
MASQUERADE_DOMAIN(dev.com)dnl

but still the problem exists..any ideas

Its solved.same thing works now. :)