OE/Hotmail emails - senders name changed to spaces/plus signs

[Nick Michell]

Hello all,

This is a strange one.

Emails sent from OE via a Hotmail account are having the senders name
changed to plus signs - for instance, "John Smith" is changed to:-
"++++ +++++". This happens in both the email header and the body of
the text, so if the sender types:-

Regards,
John

the following is received:-

Regards,
++++

If sent from Hotmail itself, the same happens *except* the space
character is substituted instead of the plus sign.

Ring any bells with anyone?

TIA.