MLDonkey clients < 2.5-16u have a bug in their LowID handling, causing them to flood the ed2k servers with connection requests. Because of that they will get banned by lugdunum servers >= 16.50 (perhaps they'll also get banned by earlier versions but I'm not sure...). This behaviour can be fixed by using the new patchpack by spiralvoice, it can be found here: http://download.berlios.de/pub/mldonkey/spiralvoice/ (version 2.5-16u)
I would additionally like to suggest that version 2.5.22 be marked stable on Portage.
Created attachment 44001 [details, diff] proposed 2.5.22 ebuild
.16-r9 now stable in portage. .16u is more stable and advanced than .22a and it is more actively patched when issues like this come up. It is recommended that you use .16u.