sysmerge complains about not valid etcXX.tgz set

[Markus Lude]

Hello,

today I updated to the latest snapshot on sparc64 (from 22nd january).
When I run sysmerge after that I got

$ sudo sysmerge -s etc55.tgz -x xetc55.tgz
        *** ERROR: /var/tmp/sysmerge.Hwq1ImlHSs/etc55.tgz is not a valid 
etcXX.tgz set

Any ideas what might go wrong here?

Regards,
Markus