Namely from the mplib maintainer, eventually! I already had a sporadic mail exchange with him where he promised to investigate the memory-leaks I had observed but he also said that he had little time at hand in these days so I switched the patience-mode on.
Last night I received three mails where he introduced his new v1.0 to me along with the tarball of this new version and, which I think is very nice, a separate testsuit. He said he had found and eliminated a few leaks so that I am now quite curious as to whether he closed all those that caused my headache.
The ChangeLog only mentions bugfixes which is a little unfortunate. I patched the mplib a little to have support for more id3v2 frames so I guess I need to re-apply these patches to his new version.
Nice that the mail arrived just before a weekend. Friday, Saturday and Sunday have always been my most productive days of a week.