Can't run aptitude

[Dennis Wicks <wix@mgssub.com>]

When I try to do nearly anything with aptitude I get

    dgwicks:~# aptitude update
    Writing extended state information... Done
    Err http://security.debian.org lenny/updates Release.gpg
      Could not connect to localhost:4001 (127.0.0.1). - connect
      (111 Connection refused)

    and similar for everything in sources.

I am pretty sure that I haven't changed anything in the last few
days since I used it the last time.

BTW I have the same problem with synaptic.

Other deb systems on my local net work just fine.

Thanks for any help!

Dennis