Wilfried: as listed in the FAQs, your second link takes the long route to the thread in question. It directs the browser to Mudcat, via the WWW, and then to the thread.
To link to a thread within Mudcat you only require the section of the URL following "mudcat.org/"
i.e "thread.cfm?threadid=65778&messages=97&page=2#1142684 "
In fact, to get the whole thread you don't need the qualifiers showing the number of messages etc. so "thread.cfm?threadid=65778" is sufficient to get the thread

CHEERS Nigel