[Typo3-dev] Bad URL encoding in Direct Mail Subscription Mails

[Jesper Weissglas]

When the Direct Mail Subscription extension gets a new subscriber, a 
mail is sent to him with 3 links to click: Accept, Reject or modify the 
subscription.

This mail is sent out with Content-Transfer-Encoding: quoted-printable.

Each link has three parts, put together in the extensions template file:
###THIS_URL######FORM_URL######SYS_<some command>###

Now since the mail encoding is QP, all '=' characters in the link (The 
form GET parameters) have to be encoded as =3D. This happends for the 
FORM_URL part, but not for the SYS_... part.

An example resulting URL:

http://www.foo.bar/index.php?id=3D2&type=3D0&cmd=3Dsetfixed&sFK=3Dapprove&rU=15&fD[_FIELDLIST]=3Duid&fD[hidden]=3D0&aC=A3b95a36

Notice how the id=, type=, cmd=, sFK= have their equal signs encoded, 
but not the rest. Or maybe the whole rest of the line is the value of 
the sFK parameter and the ampersand characters should be URL encoded as 
well?

Anyway, I am an experienced programmer, but new to Typo3, so I kind of 
got lost somewhere in the dmailer, formmail and htmlmail classes as to 
where this URL is actually put together.

Some pointers to where I could fix this, anyone?

/jesper