in kde3.5.3 for x-destop ,kmail can't send mail.only can look mail.

When I try to send I get the following error message

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Sending failed:
 Authorization failed, An error occured during authentication:
SASL(-4): no mechanism available: No worthy mechs found authentication
not supported
 The message will stay in the 'outbox' folder until you either fix the
problem (e.g. a broken address) or remove the message from the
'outbox' folder.
 The following transport protocol was used: gmx

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the following soft installed

cyrus-sasl-2.1.21