Minion sent me some links and pointed the errors out by himself:
When there's a slash in the filename (illegal character) and the link is being processed wrong.
ed2k://|file|name/name|1|d41d8cd98f00b204e9800998ecf8427e|/
The result with aMule is:
name: name
size: name -> thus invalid file size
hash: 1
Without slash everything is being processed fine.
ed2k://|file|namename|1|d41d8cd98f00b204e9800998ecf8427e|/
Through developing amule-emc I know that there's wxToken to be blamed.
Maybe one should filter all slashes except the last character, because this is the only place where it is supposed to be.