Conversion to Mime Rich Text adds character

I have a rich text field which I use to collect data. In order to export the data into html, I copy the data into another rich text field with enabled setting “Store contents as HTML with MIME”. The copy operation uses AppendRTItem to copy the data.

I am using basically the pattern as described in “Convert Notes Documents and Rich Text Fields to HTML” as described at nsftools - Lotus Notes and Domino Tips

The problem I found is that the copy operation into the the mime enabled field adds the equal character ‘=’ in regular intervals.

The added character breaks the html code.

As an example, here the designinformation of a field with the added character:

Field Name: MimeRichTextField

Data Type: MIME Part

Data Length: 8574 bytes

Seq Num: 3

Dup Item ID: 0

Field Flags: SIGN SEAL

"Content-Transfer-Encoding: quoted-printable

Content-Type: text/html; charset=“ISO-8859-1”


A LOT OF TEXT…

<=br>

Is this a known issue?

How can I prevent this from happen?