smtp error

[lynn sears]

I'm using KMail and when trying to send messages I get:

an SMTP error occured
command:  RCPT
response:   473 llbsears at ucdavis.edu  you should authenticate first
following transport protocol was used
smtp: //mail.itsquick.com:25

this does not occur when sending myself messages to
lynn at itsquick.com

I know when i used to use netscape for mail that I was prompted for my
password  to my mail account on itsquick.  I get no prompt for KMail

Ideas??