TLS negotiation in mutt

[Veljko <veljko3@gmail.com>]

Hello,

I'm using mutt with all my accounts and most of them work fine. My work email
account is hosted on exchange server and I'm using mutt's built in SMTP
functionality. I have set ssl_starttls=yes and when I'm trying to send email
I'm getting error:

"gnutls handshake: the diffie-helman prime sent by the server is not
acceptable (not long enough)

Could not negotiate TLS connection"

I tried to google something, but failed to find usable solution. 

Does anyone have some idea why this is happening and how can I fix this so I
can send emails?

Regards,
Veljko