An 8-bit locale is any locale that contains characters not present in US-ASCII. The MMDF mail system and scomail need to be configured properly for this to work. If they are not configured correctly, the 8-bit characters will not display properly at the receiving end.
The two kinds of data corruption that can be seen are as follows:
By default, MMDF strips the high-bit on outgoing mail and sendmail does not, so if you are in a locale that uses any characters that are not present in US English, you must enable 8-bit data in MMDF as follows:
confstr="charset=8bit, other confstr parameters"
Alternatively, the mmdf configuration utility generates an mmdftailor file with the 7bit parameter present. In a file of that format, you must change the ``7'' to an ``8''.
By default, scomail generates 7-bit MIME encoded characters which display in a form similar to ``=C7'' on non-MIME mailers, such as mailx. To correct this, set the X resource pass8bits to TRUE. This parameter can be found in the file /usr/lib/X11/%L/app-defaults/ScoMail.
Additionally, external mail generated by MIME mailers using the 7-bit encoding will also cause this problem. The problem must be corrected at the source or (preferably) you can use a MIME capable mailer (such as scomail) to read the mail. However, it is recommended in 8-bit locales that you always generate 8-bit data for new mail because that format is compatible with most mailers.
Also, scomail will convert ``=C7'' style mail to 8-bit encoding on replies or forwards when the message is included as text, but it will not convert them to 8-bits when the message is included as an attachment.
Conversely, if scomail is configured to send mail in the 7-bit encoding style, it will only convert 8-bit messages when the message is included as text in the reply or forward operation.