Unable to get interface configuration: 22 Invalid argument

    When I added a number of virtual interfaces to my Solaris 2.5,
    (le0:1, le0:2...), I started getting this message at every
    attempt of smtp delivery.

log/paniclog:

1996-05-09 10:19:36 0uHWlt-0005Hg-00 Unable to get interface configuration:
22 Invalid argument
1996-05-09 10:19:49 Unable to get interface configuration: 22 Invalid
argument
1996-05-09 10:19:54 Unable to get interface configuration: 22 Invalid
argument

    Ilya