[CentOS] Firefox-31 STARTTLS cipher strengh degraded?

Has anyone else experienced a degraded symmetric key exchange when using FF-31
vice FF24?

When I use FF24 then I get  a symmetric type of AES-256 (Very Strong) rating
in Calomel 0.62.  When I switch to FF31 and connect to exactly the same server
host and url then in Calomel 0.62 I see this instead:
TLS_DHE_RSA_WITH_AES_256_CBC_SHA (Very Weak).

I am not altering any of the configuration options in FF between version trials.

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James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
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